Calling upon Allah with the supplication of Dhu’n-Nun
Question

How should we call upon Allah with the supplication of Dhu’n-Nun? I mean: should I say, “La ilaha illa anta…” etc., then mention my need, or is it sufficient to say it with the intention of meeting my need?
Praise be to Allah.It was narrated that Sa‘d ibn Abi Waqqas (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “The supplication of Dhu’n-Nun when he called upon Allah when he was in the belly of the fish, is: ‘La ilaha illa anta subhanaka inni kuntu min al-zalimin (There is no god worthy of worship except You. Glory be to You; I have indeed done wrong).’ No Muslim calls upon Allah with these words for any need but Allah will answer his prayer.” Narrated by al-Tirmidhi (3505) and Imam Ahmad in al-Musnad (3/65); classed as hasan by the commentators on al-Musnad; classed as sahih by Shaykh al-Albani in Sahih al-Targhib wa’l-Tarhib (2/282).
This supplication is mentioned in the verse in which Allah, may He be exalted, says (interpretation of the meaning):
{And [remember] Dhu’l-Nun [Yunus], when he departed in anger, thinking that We would not punish him. Then he called out in the depths of darkness: There is no god worthy of worship except You. Glory be to You; I have indeed done wrong.
So We answered his prayer and delivered him from his distress; thus do We deliver the believers} [Al-Anbiya’ 21:87-88].
Shaykh ‘Abd al-Rahman al-Sa‘di (may Allah have mercy on him) said:
In the depths of darkness he called out: {‘There is no god worthy of worship except You. Glory be to You; I have indeed done wrong’}. Thus he affirmed the perfect divinity of Allah (st), declaring Him to be above any shortcomings, defects or faults, and he acknowledged his own wrongdoing and sin. Allah said: {Had he not been one of those who glorify Allah, he would have remained inside its belly until the Day they are resurrected} [as@-Saffat 37:143-144].
Hence Allah says here: {So We answered his prayer and delivered him from his distress} that is, from the hardship he had fallen into.
{thus do We deliver the believers}. This is a promise and glad tidings to every believer who falls into hardship and distress, that Allah will save him from it, and will grant him relief and alleviate his distress, because of his faith, as He did in the case of Yunus (as)."(Tafsir al-Sa‘di  p. 529).
What appears to be the case from the wording of the hadith is that limiting yourself to repeating this supplication with humility and focus of mind, with the intention that Allah may respond and meet your need, is sufficient, and there is no need to mention your need, because in the hadith the Prophet (blessings and peace of Allah be upon him) called it a supplication, and he did not advise the supplicant to mention his need.
Al-Qurtubi (may Allah have mercy on him) said:
The Prophet (blessings and peace of Allah be upon him) used to say at times of distress, “La ilaha illa Allah al-‘Azim al-Halim… (There is no god worthy of worship except Allah, the Most Great, the Most Forbearing…)” [and he would not mention his need].
Al-Tabari said: The early generations used to call upon Allah with this supplication, and they called it du‘a’ al-karb (the supplication of distress).
If it were to be asked: how can this be called a supplication when there is nothing in it to indicate that it is a supplication; rather it is glorifying and praising Allah, may He be exalted?
The answer is that this is called a supplication for two reasons:
Firstly: it may precede the supplication, and after reciting it one may offer supplication (and ask for what he needs). It says in some narrations of the hadith, “then let him offer supplication.”
Secondly: Ibn ‘Uyaynah said – when he was asked about that –: Do you not know that Allah, may He be exalted, says: “If My slave focuses on praising Me and that distracts him from asking Me for what he needs, I will give him the best of what I give to those who ask of Me.”
Umayyah ibn Abi’l-Salt said:
If someone praises you one day, his praise of you is sufficient and he does not need, after that, to ask you to help him.
I say: These are good words, and we may add to them two reasons why there is no need to ask for help:
Firstly: the one who is praised is generous, for if it is sufficient to praise him and not spell out one’s need to him, this indicates that this person is so generous that he will give to people readily and that he is extremely generous with people.
Secondly: as the one who praises someone gives precedence to praising him over his own right, which is the help he needs, then it is the duty of the one who was praised to hasten to meet his need without needing him to go through the humiliation of asking for help, by way of rewarding him for giving precedence to the one whom he praised over himself. And Allah knows best.
Among the hadiths which mention this and call it a supplication, even though there is no supplication or asking in it, is the report narrated by al-Nasa’i from Sa‘d ibn Abi Waqqas, who said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “The supplication of Dhu’l-Nun…” End quote from al-Mufhim (7/56-57).
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said:
With regard to the one with the fish [Dhu’l-Nun] and others like him, why was it appropriate in their case to describe the situation and explain it, without asking for what they needed? The answer is: because their situation was one that required admitting that what befell them of troubles was because of sin, for in principle troubles and problems result from sin, and the aim is to ward off harm, and seeking forgiveness is for the purpose of achieving that. So that is why he did not say any words asking for relief from his distress, because he realized that he was a doer of wrong and he was the one who brought that harm upon himself, so it was appropriate in his situation to say that which would help him to deal with the cause of his troubles, by acknowledging his wrongdoing, and he did not say words asking for forgiveness, because relief from trouble is the aim of the one who is in distress, and thus it (asking for forgiveness) is a secondary aim, in contrast to seeking relief from distress, which is his primary aim when there is a distressful situation. That is because it is natural for people to seek what they need of relief from harm and distress that they are suffering in the moment, before asking to be spared any harm they fear may happen in the future, which is a secondary aim. However, the primary aim in this situation was forgiveness and relief from harm, so he gave precedence to this aim, and the best way to attain that is by removing its cause. Hence he said that which would achieve his goal…"(Majmu‘ al-Fatawa  10/247-248).
If a person starts his supplication with these words, then asks for what he needs, that is also good, because offering supplication asking for what one needs is prescribed, and reciting a lot of supplications and combining them is, in principle, something that is also prescribed.
This is one of the two ways in which the scholars understand this supplication that is mentioned in this dhikr.
Al-Amir al-San‘ani (may Allah have mercy on him) said:
If it is said: this is a dhikr and not a du‘a’ (supplication), we say: It is a dhikr with which one may begin supplication, then offer whatever supplication he wants."(Al-Tanwir 6/98).
And Allah knows best.