Objection 1. It would seem that the use of wine is altogether unlawful. For without wisdom, a man cannot be in the state of salvation: since it is written (Wisdom 7:28): "God loveth none but him that dwelleth with wisdom," and further on (Wisdom 9:19): "By wisdom they were healed, whosoever have pleased Thee, O Lord, from the beginning." Now the use of wine is a hindrance to wisdom, for it is written (Ecclesiastes 2:3): "I thought in my heart to withdraw my flesh from wine, that I might turn my mind to wisdom." Therefore wine-drinking is altogether unlawful.
Objection 2. Further, the Apostle says (Romans 14:21): "It is good not to eat flesh, and not to drink wine, nor anything whereby thy brother is offended or scandalized, or made weak." Now it is sinful to forsake the good of virtue, as likewise to scandalize one's brethren. Therefore it is unlawful to make use of wine.
Objection 3. Further, Jerome says [Contra Jovin. i] that "after the deluge wine and flesh were sanctioned: but Christ came in the last of the ages and brought back the end into line with the beginning." Therefore it seems unlawful to use wine under the Christian law.
On the contrary, The Apostle says (1 Timothy 5:23): "Do not still drink water, but use a little wine for thy stomach's sake, and thy frequent infirmities"; and it is written (Sirach 31:36): "Wine drunken with moderation is the joy of the soul and the heart."
I answer that, No meat or drink, considered in itself, is unlawful, according to Matthew 15:11, "Not that which goeth into the mouth defileth a man." Wherefore it is not unlawful to drink wine as such. Yet it may become unlawful accidentally. This is sometimes owing to a circumstance on the part of the drinker, either because he is easily the worse for taking wine, or because he is bound by a vow not to drink wine: sometimes it results from the mode of drinking, because to wit he exceeds the measure in drinking: and sometimes it is on account of others who would be scandalized thereby.
Reply to Objection 1. A man may have wisdom in two ways. First, in a general way, according as it is sufficient for salvation: and in this way it is required, in order to have wisdom, not that a man abstain altogether from wine, but that he abstain from its immoderate use. Secondly, a man may have wisdom in some degree of perfection: and in this way, in order to receive wisdom perfectly, it is requisite for certain persons that they abstain altogether from wine, and this depends on circumstances of certain persons and places.
Reply to Objection 2. The Apostle does not declare simply that it is good to abstain from wine, but that it is good in the case where this would give scandal to certain people.
Reply to Objection 3. Christ withdraws us from some things as being altogether unlawful, and from others as being obstacles to perfection. It is in the latter way that he withdraws some from the use of wine, that they may aim at perfection, even as from riches and the like.
Source: Summa Theologica (New Advent)