Mu'awiyah (RAA) narrated that the Messenger of Allah (ﷺ) said regarding the one who drinks alcohol, 'If he drinks (for the first time) flog him, then if he drinks for the second time flog him, then if he drinks for the third time flog him then if he drinks for the fourth time you should kill him." Related by Ahmad and the wording is his. It is also transmitted by the four Imams.
English reference: Book 10, Hadith 1282
Arabic reference: Book 10, Hadith 1243