If the Quran is perfect and complete and contains everything needed for the laws and regulations of sharee‘ah, what need is there for the Sunnah?
Question

If the Quran is perfect and complete and contains everything needed for the laws and regulations of sharee‘ah, what need is there for the Sunnah?
Praise be to Allah.Firstly: 
The enemies of Islam are always keen to cast aspersions upon the religion of Allah, may He be exalted, in various ways and by various means. They spread their specious arguments and misguidance among the ordinary Muslims and they are followed by some of those among the Muslims who are weak in faith and ignorant. If one of these ordinary people were to give the matter a little thought, he would realise that their specious arguments are invalid and their argument is worthless. 
One of the easiest ways in which the ordinary Muslim can refute this flimsy specious argument is to ask himself: How many rak‘ahs do I pray in Zuhr? What is the minimum threshold at which zakaah becomes obligatory? These are two simple questions which no Muslim can do without knowing the answer to, but he will never find the answer to them in the Book of Allah, may He be exalted; rather he will find that Allah, may He be exalted, instructed him to pray and He instructed him to give zakaah, but how can he carry out these commands without looking to the Prophet’s Sunnah? This is impossible. Hence the Quran needs the Sunnah more than the Sunnah needs the Quran As Imam al-Awzaa‘i (may Allah have mercy on him) said:
The Book needs the Sunnah more than the Sunnah needs the Book.
al-Bahr al-Muheet by az-Zarkashi (6/11); quoted by Ibn al-Muflih al-Hanbali in al-Aadaab ash-Shar‘iyyah (2/307) from the Taabi‘i Makhool. 
We think only in the most positive terms of the brother who asked this question, and we think that he asked by way of seeking ways to refute those who say such things and claim to be respecting the Holy Quran thereby. 
Secondly: 
One of the ways in which we may refute those who claim that the Muslims have no need of the noble Sunnah, and that the Holy Quran alone is sufficient, is to note that this view is a rejection of the words of Allah, may He be exalted, in His holy Book, in many verses of which He instructed us to accept what the Prophet (blessings and peace of Allah be upon him) brought, to refrain from that which he forbade, to obey him and to accept his rulings. For example, Allah, may He be exalted, says (interpretation of the meaning):
“And whatsoever the Messenger (Muhammad (blessings and peace of Allah be upon him)) gives you, take it, and whatsoever he forbids you, abstain (from it) , and fear Allah. Verily, Allah is Severe in punishment”
[al-Hashr 59:7]
“Say: "Obey Allah and obey the Messenger, but if you turn away, he (Messenger Muhammad (blessings and peace of Allah be upon him)) is only responsible for the duty placed on him (i.e. to convey Allah’s Message) and you for that placed on you. If you obey him, you shall be on the right guidance. The Messengers duty is only to convey (the message) in a clear way (i.e. to preach in a plain way)”
[an-Noor 24:54]
“We sent no Messenger, but to be obeyed by Allah’s Leave”
[an-Nisa’ 4:64]
“But no, by your Lord, they can have no Faith, until they make you (O Muhammad (blessings and peace of Allah be upon him)) judge in all disputes between them, and find in themselves no resistance against your decisions, and accept (them) with full submission”
[an-Nisa’ 4:65]. 
So what should this person do who claims that he is content with the Quran and therefore has no need for the Sunnah with regard to these verses? How will he respond to the commands of Allah, may He be exalted, contained in them? 
This is in addition to what we said briefly first of all, which is: how can he establish the prayer which Allah, may He be exalted, enjoined upon him in His holy Book? What are the numbers of the prayers? What are the times of the prayers? What are the conditions of them being valid? What invalidates the prayer? And you may ask similar questions about zakaah, fasting, Hajj, and all the other rituals and laws of Islam. 
How will he apply the words of Allah, may He be glorified and exalted (interpretation of the meaning): “Cut off the hand of the thief, male or female, as a recompense for that which they committed, a punishment by way of example from Allah. And Allah is All-Powerful, All-Wise” [al-Maa’idah 5:38]? What is the minimum value of wealth that defines theft? From where should the hand be cut off? Is it the right hand or the left hand? What are the conditions to be met with regard to the stolen item? And you may ask similar questions about the hadd punishments for zina (fornication or adultery), slander, li‘aan and so on. 
Badr ad-Deen az-Zarkashi (may Allah have mercy on him) said: 
Ash-Shaafa‘i said in ar-Risaalah, in a chapter on the obligation of obedience to the Messenger (blessings and peace of Allah be upon him):
Allah, may He be exalted, says (interpretation of the meaning): “He who obeys the Messenger (Muhammad (blessings and peace of Allah be upon him)), has indeed obeyed Allah” [an-Nisa’ 4:80]. With regard to every obligation that Allah, may He be exalted, has enjoined in His book, such as Hajj, prayer and zakaah, were it not for the explanation of the Messenger, we would not know how to do it and it would not be possible for us to do any act of worship. Because the Messenger is of such great importance with regard to sharee‘ah, obedience to him is in fact obedience to Allah. 
Al-Bahr al-Muheet (6/7, 8) 
Similarly, the wise Muslim realises that the one who claims to be venerating the Book of Allah, may He be exalted, is one of those who are most opposed to the Quran and one of those who are drifting furthest away from the religion, because he regards the Quran alone as sufficient to establish the religion and its rulings, but he inevitably either does not follow what was brought by the Sunnah, so he becomes a disbeliever, or he does do it, therefore he is contradicting himself! 
Thirdly: 
Allah, may He be exalted, sent His Prophet (blessings and peace of Allah be upon him) with Islam, and this great blessing is not only the Quran; rather it is the Quran and the Sunnah. When Allah blessed the ummah by perfecting the religion and completing His favour upon them, what was meant was not only the sending down of the Quran; rather it was the perfection of the rulings in both the Quran and the Sunnah, based on the fact that further verses of the Holy Quran were sent down after Allah, may He be exalted, stated that He had blessed His slaves by perfecting the religion and completing His favour. 
Allah, may He be exalted, says (interpretation of the meaning):
“This day, I have perfected your religion for you, completed My Favour upon you, and have chosen for you Islam as your religion”
[al-Maa’idah 5:3]. 
Badr ad-Deen az-Zarkashi (may Allah have mercy on him) said:  
The words of Allah, may He be exalted: “This day, I have perfected your religion for you” mean: I have perfected the rulings – not the Quran – for you, because after that He revealed some verses that did not have anything to do with the rulings. 
Al-Manthoor fi’l-Qawaa‘id (1/142) 
Ibn al-Qayyim (may Allah have mercy on him) said: 
Allah, may He be glorified, explained on the lips of His Messenger, in His words and the words of His Messenger, everything that He enjoined and everything that He forbade, everything that He permitted and everything that He prohibited, and everything that He pardoned. Thus His religion is perfect, as Allah, may He be exalted, says (interpretation of the meaning):
“This day, I have perfected your religion for you, completed My Favour upon you”
[al-Maa’idah 5:3]. 
I‘laam al-Muwaqqi‘een (1/250) 
Fourthly: 
The Prophet (blessings and peace of Allah be upon him) stated that the Sunnah that he brought is like the Quran in that it is from Allah, may He be exalted, in that it constitutes proof, and in that it is binding upon people; and he warned against being content only with what is in the Quran in following what it enjoins and refraining from what it forbids. He gave an example of something that is proven to be haraam according to the Sunnah but is not mentioned in the Quran; in fact in the Quran there is a suggestion that it may be permissible. All of that appears in a single saheeh hadith. 
It was narrated from al-Miqdaam ibn Ma‘di Karib from the Messenger of Allah (blessings and peace of Allah be upon him) that he said: “Verily, I have been given the Book and something like it with it, but soon a man will be lying replete on his couch and he will say: You should adhere to this Quran. Whatever you find is permitted in it, take it as permissible, and whatever you find forbidden in it, take it as forbidden. Verily, the (meat of) tame donkeys is not permissible to you, nor is (the meat of) every animal that has fangs.” 
Narrated by Abu Dawood (4604); classed as saheeh by al-Albaani in Saheeh Abi Dawood. 
This is what the Sahaabah (may Allah be pleased with them) understood from the religion of Allah, may He be exalted: 
It was narrated that ‘Abdullah said: May Allah curse those who do tattoos and those who have tattoos done, those who pluck theirs eyebrows, and those who file teeth for the purpose of beautification, changing the creation of Allah. News of that reached a woman of Banu Asad who was called Umm Ya‘qoob, and she came to him and said: I have heard that you cursed such and such, and such and such. He said: Why should I not curse those whom the Messenger of Allah (blessings and peace of Allah be upon him) cursed, and those who are cursed in the Book of Allah? The woman said: I have read the Mus-haf from cover to cover and I did not find in it what you say. He said: If you had read it you would have found it. Have you not read the verse: ‘And whatsoever the Messenger (Muhammad (blessings and peace of Allah be upon him)) gives you, take it; and whatsoever he forbids you, abstain (from it)’ [al-Hashr 59:7]? She said: Yes. He said: And he did indeed forbid that. She said: I think your family do that. He said: Go and look. So she went and looked, and she did not see anything of what she expected to see. He said: If that were the case, she would not live with us. 
Narrated by al-Bukhaari (4604) and Muslim (2125) 
This is what the Taabi‘een and the leading scholars of Islam understood about the religion of Allah, may He be exalted, and they did not know anything else: which is that there is no difference between the Quran and Sunnah with regard to quoting evidence and constituting binding proof, and that the Sunnah explains and clarifies what is in the Quran. 
Al-Awzaa‘i said, narrating from Hassaan ibn ‘Atiyyah: Jibreel used to come down to the Messenger of Allah (blessings and peace of Allah be upon him), and the Sunnah explains the Quran. 
Ayyoob as-Sakhtiyaani said: If a man is told about the Sunnah and he says, “Forget about that and tell us about the Quran,” then you should know that he is misguided and is trying to mislead others. 
Al-Awzaa‘i said: Allah, may He be exalted, says (interpretation of the meaning): “He who obeys the Messenger (Muhammad (blessings and peace of Allah be upon him)), has indeed obeyed Allah” [an-Nisa’ 4:80] and “And whatsoever the Messenger (Muhammad (blessings and peace of Allah be upon him)) gives you, take it” [al-Hashr 59:7]. 
Al-Awzaa‘i said: al-Qaasim ibn Mukhaymirah said: Whatever was haraam at the time when the Messenger of Allah (blessings and peace of Allah be upon him) died is haraam until the Day of Resurrection, and whatever was halaal at the time when he died is halaal until the Day of Resurrection. 
See: al-Aadaab ash-Shar‘iyyah (2/307) 
Badr ad-Deen az-Zarkashi (may Allah have mercy on him) said: 
Al-Haafiz ad-Daarimi said: He (the Prophet (blessings and peace of Allah be upon him)) said: “I have been given the Quran and I have been given something (else) like it.” There are some hadiths that speak of matters of which the Quran did not say anything but they can only be in accordance with what Allah willed, such as the prohibition on the flesh of tame donkeys and every wild animal that has fangs, which are not mentioned in the Book. 
With regard to the hadith that was narrated via Thawbaan, which speaks of the command to check hadiths against the Quran, ash-Shaafa‘i said in ar-Risaalah:
It was not narrated by anyone whose hadith was proven to be sound with regard to any matter, minor or major. The imam (leading scholar) of hadith, Yahya ibn Mu‘een, stated that it is mawdoo‘ (fabricated). It was also classed as having been fabricated by the heretics. Ibn ‘Abd al-Barr said in Jaami‘ Bayaan al-‘Ilm: ‘Abd ar-Rahmaan ibn Mahdi said: The heretics and the Khaarijis fabricated the hadith “Whatever comes to you from me, check it against the Book of Allah; if it is in accordance with the Book of Allah, then I said it, but if it goes against it, then I did not say it.” Al-Haafiz said: This is not saheeh. But some people agreed to check that hadith against the Book of Allah, and said: We checked it against the Book of Allah and found it to be contrary to the Book, because we did not find anything in it to say that no hadith should be accepted except that which is in harmony with the Book; rather we found in it the command to obey him, and the warning against going against hiscommands is in itself a ruling. End quote. 
Ibn Hibbaan said in his Saheeh concerning the words of the Prophet (blessings and peace of Allah be upon him), “Convey from me, even if it is one verse”: This indicates that the Sunnah may also be described as “verses”. 
Al-Bahr al-Muheet (6/7, 8) 
Fifthly: 
The scholars have mentioned several ways in which the Sunnah explains the Quran. For example, it is in accordance with what is in the Quran; it restricts what is mentioned in broad terms, specifies what is mentioned in general terms, expands upon what is mentioned in brief, abrogates some rulings, and introduces some new rulings. Some scholars summed that up in three points. 
Ibn al-Qayyim (may Allah have mercy on him) said: 
What every Muslim must believe is that there is nothing in the saheeh Sunnah of the Messenger of Allah (blessings and peace of Allah be upon him), not even a single Sunnah, that is contrary to the Book of Allah. Rather the Sunnah, in relation to the Book of Allah, falls into three categories: 
1.that which is in agreement with and states the same as that which is stated in the revealed Book
2.that which explains the Book and clarifies what Allah meant thereby, restricting that which is mentioned in broad terms
3.that which contains a ruling that is not mentioned in the Book, so it explains and introduces something new.
It is not permissible to deny any of these three categories, and there is no fourth category of the Sunnah in relation to the Book of Allah. 
Imam Ahmad objected to those who said that “The Sunnah may overrule the Book” and he said: Rather the Sunnah explains and clarifies the Book. 
What Allah and His Messenger testify to is that there is no single saheeh report from the Messenger of Allah (blessings and peace of Allah be upon him) that contradicts the Book of Allah or goes against it at all. How could that be, when the Messenger of Allah (blessings and peace of Allah be upon him) is the one who explains the Book of Allah, it was revealed to him, Allah guided him by means of it, he was enjoined to follow it and he is the most knowledgeable of all people about its interpretation and meanings?! 
If it were permissible to reject a Sunnah of the Messenger of Allah (blessings and peace of Allah be upon him) on the basis of what a person understands of the apparent meanings of the Quran, then most of the hadiths would be rejected and the Sunnah would be abolished completely. 
There is no one who is presented with proof from the saheeh hadiths that is contrary to the view of his madhhab or sect, but he is able to cling to the general meaning or broad meaning of a verse, and he says: This report from the Sunnah is contrary to this general meaning or broad meaning, therefore it is not to be accepted. 
Even the Raafidis follow this exact approach in rejecting proven and mutawaatir hadiths. Thus they reject the words of the Prophet (blessings and peace of Allah be upon him), “We (Prophets) are not to be inherited from; what we leave behind is charity”, and they say: This hadith is contrary to the Book of Allah, because Allah, may He be exalted, says (interpretation of the meaning): “Allah commands you as regards your children’s (inheritance); to the male, a portion equal to that of two females” [an-Nisa’ 4:11]. 
The Jahamis rejected many saheeh hadiths that affirm the divine attributes, based on the apparent meaning of the verse (interpretation of the meaning): “There is nothing like unto Him” [ash-Shoora 42:11].
The Khaarijis rejected the hadiths that speak of intercession, and the emergence from Hell of those among the monotheists who committed major sins, based on their understanding of the apparent meaning of the Quran. 
The Jahamis rejected the hadiths that speak of seeing Allah in the Hereafter, even though there are so many saheeh hadiths to that effect, on the basis of their understanding of the apparent meaning of the verse in which Allah, may He be exalted, says (interpretation of the meaning): “No vision can grasp Him” [al-An‘aam 6:103]. 
The Qadaris rejected the proven hadiths that speak of the divine decree, based on their understanding of the apparent meaning of the Quran. 
Each sect rejected what it rejected of the Sunnah on the basis of their understanding of the apparent meaning of the Quran. 
So either we should reject all of these reports of the Sunnah, or we should accept all of them and not reject any of them on the basis of what may be understood from the apparent meaning of the Quran. But rejecting some of them and accepting others on the basis of this argument is an obvious contradiction. 
There is no one who rejects a hadith on the basis of his understanding of the apparent meaning of the Quran but he accepts many times more than that. 
Imam Ahmad, ash-Shaafa‘i and others denounced those who rejected the hadiths that speak of the prohibition on all wild animals that have fangs, on the basis of the apparent meaning of the verse in which Allah, may He be exalted, says (interpretation of the meaning): “Say (O Muhammad (blessings and peace of Allah be upon him)): "I find not in that which has been inspired to me anything forbidden to be eaten…” [al-An‘aam 6:145]. 
The Prophet (blessings and peace of Allah be upon him) denounced those who merely reject his Sunnah that is not mentioned in the Quran, even though they did not claim that it was contrary to the Quran. So how about one who claims that his Sunnah is contrary to the Quran and opposed to it? 
At-Turuq al-Hukamiyyah (65-67) 
Shaykh al-Albaani (may Allah have mercy on him) wrote an essay entitled Manzilat as-Sunnah fi’l-Islam wa Bayaan annahu la yustaghna ‘anha bi’l-Quran (The status of the Sunnah in Islam, and that we cannot do without it and rely only on the Quran), in which he said: 
You all know that Allah, may He be blessed and exalted, chose Muhammad (blessings and peace of Allah be upon him) to be His Prophet and He selected him to convey His message. So He sent down to him His Book, the Holy Quran, in which – among other things – He instructed him to explain it to people. Allah, may He be exalted, said (interpretation of the meaning): “And We have also sent down unto you (O Muhammad (blessings and peace of Allah be upon him)) the reminder and the advice (the Quran), that you may explain clearly to men what is sent down to them” [an-Nahl 16:44]. What I think is that the explanation referred to in this verse include two types of explanation: 
-1-
Conveying the words verbatim, which is conveying the Quran and not concealing it. This means delivering it to the ummah as Allah, may He be Blessed and exalted, sent it down to the heart of the Prophet (blessings and peace of Allah be upon him). This is what is meant by the verse in which Allah, may He be exalted, says (interpretation of the meaning): “O Messenger (Muhammad (blessings and peace of Allah be upon him))! Proclaim (the Message) which has been sent down to you from your Lord” [al-Maa’idah 5:67]. ‘Aa’ishah (may Allah be pleased with her) said, according to a report narrated from her: Whoever told you that Muhammad concealed anything that he was instructed to convey has told the gravest of lies against Allah. Then she recited the verse mentioned. Narrated by al-Bukhaari and Muslim. According to a report narrated by Muslim, she said: If the Messenger of Allah (blessings and peace of Allah be upon him) had concealed anything that he was instructed to convey, he would have concealed the verse in which Allah, may He be exalted, says (interpretation of the meaning): “And (remember) when you said to him (Zaid bin Haarithah the freed slave of the Prophet (blessings and peace of Allah be upon him)) on whom Allah has bestowed Grace (by guiding him to Islam) and you (O Muhammad (blessings and peace of Allah be upon him)too) have done favour (by manumitting him) "Keep your wife to yourself, and fear Allah." But you did hide in yourself (i.e. what Allah has already made known to you that He will give her to you in marriage) that which Allah will make manifest, you did fear the people (i.e., Muhammad (blessings and peace of Allah be upon him) married the divorced wife of his manumitted slave) whereas Allah had a better right that you should fear Him” [al-Ahzaab 33:37]. 
-2-
Explaining the meanings of the words, phrase or verse for which the ummah needs an explanation. This mostly applies to verses which speak in brief, general or broad terms. In such cases the Sunnah comes and expands upon that which is mentioned in brief, specifies that which is mentioned in general terms, and restricts that which is mentioned in broad terms. This may be by means of what the Prophet (blessings and peace of Allah be upon him) said, or by means of what he did or approved of. 
The verse in which Allah, may He be exalted, says (interpretation of the meaning): “Cut off the hand of the thief, male or female” [al-Maa’idah 5:38] is a good example of this. The word thief is a broad term, as is the word hand. But the hadith explains the meaning of the former, and restricts it to the thief who steals property worth one quarter of a dinar or more, as the Prophet (blessings and peace of Allah be upon him) said: “There is no cutting off of the hand except for property worth one quarter of a dinar or more.” Narrated by al-Bukhaari and Muslim. The latter [hand, as the Arabic word yad may refer to the hand or the entire forearm] is explained by the action of the Prophet (blessings and peace of Allah be upon him) or by the actions of his companions of which he approved. They used to cut off the hand of the thief from the wrist joint, as is well-known in the books of hadith. The hadiths also explain what is meant by the hand as mentioned in the verse on tayammum – “and rub therewith your faces and hands (Tayammum)” [an-Nisa’ 4:43, al-Maa’idah 5:6] – as also referring to the hand [as opposed to the entire forearm], as the Prophet (blessings and peace of Allah be upon him) said: “Tayammum means striking [the ground or other clean, dusty surface] with the hands and then wiping the face and hands.” Narrated by Ahmad, al-Bukhaari, Muslim and others from the hadeeth of ‘Ammaar ibn Yaasir (may Allah be pleased with him). 
There follow some other verses which cannot be understood correctly except by means of the Sunnah:
 -1-
“It is those who believe (in the Oneness of Allah and worship none but Him Alone) and confuse not their belief with Zulm (wrong i.e., by worshipping others besides Allah), for them (only) there is security and they are the guided”
[al-An‘aam 6:82]. 
The companions of the Prophet (blessings and peace of Allah be upon him) understood the word zulm (wrong or wrongdoing) in general terms, which included every wrong deed, even if it is minor. Hence they were confused about this verse and they said: O Messenger of Allah, which of us has never confused his belief with wrongdoing? But he (blessings and peace of Allah be upon him) said: “That is not what it means; rather it refers to shirk (ascribing partners to Allah). Have you not heard the words of Luqmaan, ‘Verily! Joining others in worship with Allah is a great Zulm (wrong) indeed’ [Luqmaan 31:13]?” Narrated by al-Bukhaari and Muslim and others. 
-2-
“And when you (Muslims) travel in the land, there is no sin on you if you shorten your Salat (prayer) if you fear that the disbelievers may attack you”
[an-Nisa’ 4:101].
The apparent meaning of this verse suggests that shortening prayers when travelling is allowed only on condition that there is fear. Hence some of the Sahaabah (may Allah be pleased with them) asked the Messenger of Allah (blessings and peace of Allah be upon him): Why are we still shortening the prayer when we are safe now? He said: “That is a charity that Allah has bestowed upon you, so accept His charity.” Narrated by Muslim. 
-3-
“Forbidden to you (for food) are: Al-Maytatah (the dead animals - cattle-beast not slaughtered), blood…”
[al-Maa’idah 5:3]. 
The hadith explains that “dead meat” [that which is not slaughtered in the prescribed manner] of locusts and fish, and liver and spleen, which come under the category of blood, are halaal. The Prophet (blessings and peace of Allah be upon him) said: “Two types of dead meat and two types of blood have been made permissible to us: locusts and fish (of all types), and liver and spleen.” Narrated by al-Bayhaqi and others with both marfoo‘ and mawqoof isnaads. This isnaad of the mawqoof (i.e., the name of the Sahaabi is missing from the isnaad) version is saheeh, and it comes under the same ruling as a marfoo‘ hadith (one in which the chain of narrators  goes all the way back to the Prophte (blessings and peace of Allah be upon him)), because this could not have been said on the basis of the personal view of any Sahaabi. 
-4-
“Say (O Muhammad (blessings and peace of Allah be upon him)): "I find not in that which has been inspired to me anything forbidden to be eaten by one who wishes to eat it, unless it be Maytatah (a dead animal) or blood poured forth (by slaughtering or the like), or the flesh of swine (pork, etc.) for that surely is impure, or impious (unlawful) meat (of an animal) which is slaughtered as a sacrifice for others than Allah (or has been slaughtered for idols, etc., or on which Allah’s Name has not been mentioned while slaughtering)”
[al-An‘aam 6:145]. 
But the Sunnah prohibits some things that are not mentioned in this verse, such as when the Prophet (blessings and peace of Allah be upon him) said: “Every wild animal that has fangs, and every bird that has talons, is haraam.” And there are other hadiths that prohibit certain foods, such as when the Prophet (blessings and peace of Allah be upon him) said on the day of Khaybar: “Verily Allah and His Messenger forbid you to eat the flesh of tame donkeys, for it is an abomination.” Narrated by al-Bukhaari and Muslim. 
-5-
“Say (O Muhammad (blessings and peace of Allah be upon him)): "Who has forbidden the adornment with clothes given by Allah, which He has produced for his slaves, and At-Taiyibat (all kinds of Halal (lawful) things) of food?”
[al-A‘raaf 7:32].
 Here too the hadith explains that there are some kinds of adornment that are prohibited. It is proven that the Prophet (blessings and peace of Allah be upon him) came out to his Companions one day with a piece of silk in one hand and a piece of gold in the other, and he said: “These two are prohibited for the males of my ummah but they are permissible for the females.” Narrated and classed as saheeh by al-Haakim. 
There are many similar and well-known hadiths in as-Saheehayn and elsewhere, and there are many more similar examples that are well known to the scholars of hadith and fiqh. 
From the above it is clear to us that the Sunnah is of great importance in Islamic legislation. If we look again at the examples mentioned – let alone others that we have not mentioned – we will be certain that there is no way to understand the Holy Quran unless that is alongside the Sunnah. 
Manzilat as-Sunnah fi’l-Islam (p. 4-12)  
We advise you to read this essay by Shaykh al-Albaani (may Allah have mercy on him), as it deals with the exact same topic as your question. 
Thus it should be clear: 
That it is not permissible for anyone to separate the Quran from the Sunnah when it comes to confirming rulings and their binding nature upon the one who is accountable. The one who does that is indeed going against what the Quran contains of the commands to obey the Messenger (blessings and peace of Allah be upon him), follow his Sunnah and refrain from what he forbids. The Prophet’s Sunnah came to reinforce what is in the Quran and to explain it, restrict what it mentions in broad terms and specify what it mentions in general terms. It also independently introduced new rulings. It is binding upon the Muslim to follow all of that. 
Finally: 
Assume that we regard this matter as an issue of dispute between us and our opponents who say that we should be content with the Quran alone. We say: In the Holy Quran we are instructed, in the event of dispute, to refer to the Quran and the Sunnah! Allah, may He be exalted, says (interpretation of the meaning):
“O you who believe! Obey Allah and obey the Messenger (Muhammad (blessings and peace of Allah be upon him)), and those of you (Muslims) who are in authority. (And) if you differ in anything amongst yourselves, refer it to Allah and His Messenger (blessings and peace of Allah be upon him), if you believe in Allah and in the Last Day. That is better and more suitable for final determination”
[an-Nisa’ 4:59]. 
So what will our opponent do with this Quranic proof? If he accepts it, he will refer to the Sunnah, and thus invalidate his view. But if he does not refer to the Sunnah, then he will be going against the Quran, which he claims is sufficient with no need for the Sunnah!