A Christian is asking about the prohibition on alcohol
Question

Why does Islam forbid alcohol whilst promising the people of Paradise that they will drink wine there?.
Praise be to Allah.We have already listed some of the evil consequences that result from drinking alcohol, which are the reason why drinking it is absolutely forbidden in the religion of Allah. See for example question no 40882. 
But the questioner – may Allah guide us and him to knowledge of the truth – thinks that the prohibition on alcohol in this world, and the promise to the believers that they will enjoy it in Paradise, is a contradiction or fault in the religion of Allah, or at best he is confused by this. 
Allah forbid that there should be any contradiction in his Book or His laws, for He is the All-Knowing, All-Wise, All-Aware. Contradictions come from others, not from Him, may He be exalted. Allah says (interpretation of the meaning): 
“Do they not then consider the Quran carefully? Had it been from other than Allah, they would surely, have found therein many a contradiction” [Al-Nisa’ 4:82]
Contradictions come from human beings when they try to criticize the revealed words, and from their misunderstanding when they fail to grasp the intended meaning or the wisdom behind the words. 
The Book of Allah is protected by Him, as He says (interpretation of the meaning): 
“Verily, We, it is We Who have sent down the Dhikr (i.e. the Quran) and surely, We will guard it (from corruption)” [Al-Hijr 15:9]. 
With regard to other books (scriptures), Allah has not guaranteed to preserve them, rather He commanded their people to guard them, but they altered them and changed them, so no one longer has any doubt that they have been changed from the form in which Allah revealed them. Indeed anyone among the people of these Books who has the slightest knowledge does not claim that this is how they were revealed from God or that the Messiah conveyed them like this during his lifetime. See question no. 47516. 
Now let us return to the question and ask the questioner: 
Are you objecting to the prohibition on alcohol in this world? Do you want it to be permitted as it will be a delight for the people of Paradise? In that case we ask you: Wasn’t alcohol forbidden in your holy Book, and is that not mentioned repeatedly in the Old Testament in which you believe? If you do not know about that, then listen: 
“Woe to those who are champions at drinking wine and champions at mixing drinks”
Isaiah 5:22 (New International Version) 
“Do not join those who drink too much wine or gorge themselves on meat, for drunkards and gluttons become poor”
Proverbs 23:20-21 (New International Version) 
“Then the LORD said to Aaron: ‘You and your sons are not to drink wine or other fermented drink whenever you go into the Tent of Meeting, or you will die. This is a lasting ordinance for the generations to come. You must distinguish between the holy and the profane, between the unclean and the clean.’”
Leviticus 10:8-10 (New International Version) 
This is sufficient evidence for anyone who is wise; as for discussing these verses in detail, we do not have room to do so here. 
Even in the New Testament of your holy Book, there remain some verses which point to that: 
“But now I am writing to you that you must not associate with anyone who calls himself a brother but is sexually immoral or greedy, and idolater or a slanderer, a drunkard of a swindler. With such a man do not even eat.”
1 Corinthians 5:11 (New International Version) 
“Do you not know that the wicked will not inherit the kingdom of God? Do not be deceived: Neither the sexually immoral nor idolaters nor adulterers nor male prostitutes nor homosexual offenders nor thieves nor the greedy nor drunkards nor slanderers nor swindlers will inherit the kingdom of Gos.”
1 Corinthians 6:9-10 (New International Version) 
“Do not get drunk with wine, which leads to debauchery. Instead, be filled with the Spirit.”
Ephesians 5:18 (New International Version) 
And there any many similar verses. 
“Then which of the Blessings of your Lord will you both (jinn and men) deny?” [Al-Rahmaan 55:13]
If you claim, as you do, that this prohibition was abrogated and that it became permissible for you, then why do you object to the idea that the Quran abrogated that permission and that Allah has forbidden it to people in this world? 
Or are you objecting to the fact that it will become a delight in the Hereafter after it was forbidden in this world? Do you want it to be forbidden in both realms? 
In that case, it remains for us to ask you: if you accept that the prohibition of alcohol in this world was abrogated, so it became permissible – as you claim – then is it not more appropriate that you should accept that in the Hereafter? Even though the Hereafter is not a place of obligations, rather it is the place of delight for the people of Paradise and the torment of Hell for the people of the Fire. 
But we say this simply for the sake of argument, to show to him that he was being fair to his opponent when he did not look at what he has (in the Bible). 
But if the questioner really wants to know the truth, then the truth is simpler than that, for it is light, and in that case we say to him: 
Allah has forbidden alcohol because it is an evil abomination, of the Devil’s handiwork; it destroys the mind of the one who drinks it and distracts him from worshipping and obeying Allah, and leads him to disobey Him, and it generates enmity and hatred in the hearts of the believers. Allah says (interpretation of the meaning): 
“O you who believe! Intoxicants (all kinds of alcoholic drinks), and gambling, and Al‑Ansaab (stone altars for sacrifices to idols etc), and Al‑Azlaam (arrows for seeking luck or decision) are an abomination of Shaytaan’s (Satan’s) handiwork. So avoid (strictly all) that (abomination) in order that you may be successful.
91. Shaytaan (Satan) wants only to excite enmity and hatred between you with intoxicants (alcoholic drinks) and gambling, and hinder you from the remembrance of Allah and from As‑Salaah (the prayer). So, will you not then abstain?” [Al-Maa’idah 5:90-91]
The Messenger of Allah (peace and blessings of Allah be upon him) said: “Every intoxicant is khamr and all khamr is haraam.” Saheeh Muslim, 2003. 
This is what it says in your holy Book: 
“Then the LORD said to Aaron: ‘You and your sons are not to drink wine or other fermented drink ... You must distinguish between the holy and the profane, between the unclean and the clean.’”
Leviticus 10:8-10 (New International Version) 
As for the wine of the Hereafter, it is delightful and is free of all the filth and impurities of worldly wine. Paradise is the abode of the good and pure, and there is nothing in it but good things. Our Lord says (interpretation of the meaning): 
“Round them will be passed a cup of pure wine —
46. White, delicious to the drinkers.
47. Neither will they have Ghoul (any kind of hurt, abdominal pain, headache, a sin) from that nor will they suffer intoxication therefrom” [Al-Saaffaat 37:45-47]
They will not suffer any kind of hurt, pain, or headaches, and it will not destroy their wealth. 
The wine of the Hereafter bears no resemblance to the wine of this world except in name. As for its real nature, no eye has seen, no ear has heard, nor has it entered the heart of man. Our Lord says (interpretation of the meaning): 
“No person knows what is kept hidden for them of joy as a reward for what they used to do” [Al-Sajdah 32:17]
The one who contaminate himself with the wine of this world deserves to be denied the wine of the Hereafter. The Messenger of Allah (peace and blessings of Allah be upon him) said: “Every intoxicant is khamr and every intoxicant is haraam. Whoever drinks wine in this world and dies having persisted in drinking it and not having repented, will never drink it in the Hereafter.” 
Saheeh Muslim, 2003. 
We ask Allah to guide you to the truth and help you to give up specious arguments. 
And Allah is the source of strength, and there is no lord but He.