Drinking wine [and other alcoholic beverages] is unlawful. In some traditions, it is considered one of the gravest sins. It has been reported from Imam al-Ṣādiq (ʿA) that he said, ‘Wine is the root of evil and the origin of sins. A person who drinks wine loses his intellect, and at that moment, he does not know Allah, fear any sin, keep the respect of anyone, observe the rights of his near relatives, or turn away from openly obscene acts.
If he takes a sip of it, Allah the Exalted, the angels, the Prophets, and the believers curse him. And if he drinks until he becomes intoxicated, the spirit of belief and the ability to know Allah leave him and the spirit of filthy evil takes their place. His prayers (ṣalāh) are not accepted for forty days (even though it is obligatory (wājib) on him to perform his prayers and his prayers are valid (ṣaḥīḥ)).’