Fiqh-us-Sunnah Volume 1, Purification and Prayer, Fiqh 1.012A.

According to most scholars, alcohol is impure. Says Allah in the Qur’an, “Alcohol, games of chance, idols and divining arrows are only an infamy of Satan’s handiwork.” Some scholars say that it is pure, for they take the meaning of rajis in its abstract sense as describing alcohol and whatever is related to it. This is not labelled as impure in a definite, sensory way. Says Allah, “Stay away from the impurities of idols.” Idols are impure in the abstract sense, and they are considered impure if one touches them. The explanation of the preceding verse is that they are a tool of Satan, for they cause enmity and hatred and keep people away from the remembrance of Allah and prayer. In Subul as-Salaam it says, “Their origin is pure and their being prohibited does not mean that the object itself is impure. For example, hashish is prohibited but it is pure. But, something impure is not necessarily prohibited. Every impure thing is prohibited, but not vice-versa. That is because of the ruling that something impure cannot be touched under any circumstances. If a ruling says that something is impure, it is also prohibited. This differs from a ruling that something is prohibited. For example, it is forbidden to wear silk and gold, but they are absolutely pure by consensus.” If one understands that, then the prohibition of alcohol does not necessarily  entail its also being considered impure: it needs some other evidence to prove that it is impure. If not, then we are left with the original position that it is pure. If one claims other than that, he must substantiate it.