Intoxicants are forbidden by way of the Qur'an and the Sunnah and Ijmaa' (consensus) of the Muslims. It's forbiddance is something which is well known in the religion of Islam by necessity, for this reason the scholars رحمهم الله say,
Whoever rejects the prohibition of (alcohol/intoxicants) while he is living amongst the Muslims then he is an apostate.
Meaning, an apostate from the religion of Islam because he has rejected that which is known by the religion by necessity; because of that he becomes an apostate, just like if he rejects the prohibition of fornication or the obligation of the five daily prayers and the likes of it.
Likewise, knowledge and the intellect require that (alcohol) is forbidden because it causes one to be like the insane -Allah's refuge is sought-. Because of (alcohol/intoxicants a man) divorces his wives or perhaps (he) even kills his children or does an illicit sexual act with one who is forbidden for him.
I read some years ago in a magazine and I do not like to mention where it was issued, that a youth entered upon his mother at one o'clock in the morning, (after midnight) and (tried) to seduce her. He wanted to do an illicit sexual act with her -Allah's refuge is sought- (but) she refused so then he grabbed a knife and threatened (her) saying, "If you don't allow me to have (relations) with you I will kill myself."
Sympathy overcame her so she enabled him to and -Allah's refuge is sought- he fornicated with (his mother).
The next morning it was as if his conscience caught up with him because he went to his mother and said, "O Mother did I do such and such?" She said "No" fearing for him, so he took an oath that if she doesn't inform him he will do such and such. She then informed him (what he did) so he quickly left from among her and took a tin of gas, entered the bathroom then poured the gas on himself then set himself on fire. -Allah's refuge is sought-
So look, he (started by) drinking alcohol, then fornicated with his mother and at the end killed himself; because of this it comes in a narration, naming alcohol as "the mother of all filthy (evil and unlawful) things." (an-Nasaai)
And another hadeeth "the key to all evil." (Ibn Majah)