Verse 23 is its own section.
 
 1 Timothy 5:23
 Drink no longer water, but use a little wine for thy stomach's sake and thine often infirmities.
 
ADVICE FOR TIMOTHY
1 Timothy 5:23
 
Stop drinking only water, and use a little wine for the sake of your stomach, to help your frequent illnesses.
 
THIS sentence shows the real intimacy of these letters. Amid the affairs of the Church and the problems of administration, Paul finds time to slip in a little bit of loving advice to Timothy about his health.
 
There had always been a strain of self-denial in Jewish religion. When a man took the Nazirite vow (Numbers 6:1–21), he was pledged never to taste any of the product of the vine: ‘They shall separate themselves from wine and strong drink; they shall drink no wine vinegar or other vinegar, and shall not drink any grape juice or eat grapes, fresh or dried. All their days as Nazarites they shall eat nothing that is produced by the grapevine, not even the seeds or the skins’ (Numbers 6:3–4). The Rechabites were also pledged to abstain from wine. The Book of Jeremiah tells how Jeremiah went and set before the Rechabites wine and cups: ‘But they answered, “We will drink no wine; for our ancestor Jonadab son of Rechab commanded us, ‘You shall never drink wine, neither you nor your children; nor shall you ever build a house, or sow seed; nor shall you plant a vineyard’”’ (Jeremiah 35:6–7). Now, Timothy was on one side a Jew – his mother was Jewish (Acts 16:1) – and it may well be that from his mother he had inherited this abstemious  (ăb-stē'mē-əs, əb-) [eating and drinking in moderation] way of living. On his father’s side, he was a Greek. We have already seen that behind the Pastorals there is the heresy of Gnosticism, which saw all matter as evil and often resulted in self-denial; and it may well be that Timothy was unconsciously influenced by this Greek abstinence as well.
 
Here we have a great truth which Christians forget at their peril – that we dare not neglect the body, for often spiritual dullness and sterility come from the simple fact that the body is tired and neglected. No machine will run well unless it is cared for, and neither will the body. We cannot do Christ’s work well unless we are physically fit to do it. There is no virtue – rather the reverse – in neglect of or contempt for the body. Mens sana in corpore sano, a healthy mind in a healthy body, was the old Roman ideal – and it is the Christian ideal too.
 
This is a text which has much troubled those who are advocates of total abstinence. It must be remembered that it does not give anyone a license to indulge in drink to excess; it simply approves the use of wine where it may be medicinally helpful. If it does lay down any principle at all, E. F. Brown has well stated it: ‘It shows that while total abstinence may be recommended as a wise counsel, it is never to be enforced as a religious obligation.’ Paul is simply saying that there is no virtue in the self-denial which does the body more harm than good. ~Barclay commentaries
 
Now to the commentaries.
 
First from the Matthew Henry Concise Commentary:
 
1 Timothy 5:23
The apostle also charges Timothy to take care of his health. As we are not to make our bodies masters, so neither slaves; but to use them so that they may be most helpful to us in the service of God. ~Matthew Henry CC
 
The John Darby Synopsis also speaks to the verse in the overall sense:
 
Timothy's habitual temperance is here seen: weak in body, the apostle recommends him to use his liberty by taking a little wine — a pleasing instance of grace. We have here a proof of the habits of this faithful servant. The Spirit shows us how carefully he kept himself from exciting or satisfying his passions in the least thing (at the same time that there is perfect liberty to use everything that is good when there is a true reason for it) and also the apostle's tender interest in his fellow-labourer in the gospel. It is a little parenthesis attached to the expression, " be not a partaker of other men's sins," but it has great beauty. This affectionate watchfulness became the apostle; he desired holiness in his representative, but he well knew how to respect Timothy, and to maintain the decorum which he had enjoined, and to exhibit his heartfelt tenderness. ~John Darby Snopsis
 
The Geneva Bible Translation Notes says: "let the elders have consideration for their health, in their diet." ~Geneva
 
For the other commentaries, the verse is in four parts:
 
1] Drink no longer water.
2] But use a little wine.
3] For thy stomach's sake.
4] And thine often infirmities.
 
1] Drink no longer water.
 
Drink no longer water - I suppose the thought of Timothy's trials called to mind a sense of his physical condition. Hence, he gives a medical prescription. The water of that region is not good. The writer well remembers a fearfully sick day that he passed at Ephesus in 1889, due to the water. Paul, hence, advises that instead, he try the light wines, with only the smallest percentage of alcohol. The prescription is not of a beverage, but of a remedy for an invalid. ~People's New Testament
 
Drink no longer water - There has been much difficulty felt in regard to the connection which this advice has with what precedes and what follows. Many have considered the difficulty to be so great that they have supposed that this verse has been displaced, and that it should be introduced in some other connection. The true connection, and the reason for the introduction of the counsel here, seems to me to be this: Paul appears to have been suddenly impressed with the thought - a thought which is very likely to come over a man who is writing on the duties of the ministry - of the arduous nature of the ministerial office. He was giving counsels in regard to an office which required a great amount of labor, care, and anxiety. The labors enjoined were such as to demand all the time; the care and anxiety incident to such a charge would be very likely to prostrate the frame, and to injure the health. Then he remembered that Timothy was yet but a youth; he recalled his feebleness of constitution and his frequent attacks of illness; he recollected the very abstemious (ăb-stē'mē-əs, əb-) habits which he had prescribed for himself, and, in this connection, he urges him to a careful regard for his health, and prescribes the use of a small quantity of wine, mingled with his water, as a suitable medicine in his case. Thus considered, this direction is as worthy to be given by an inspired teacher as it is to counsel a man to pay a proper regard to his health, and not needlessly to throw away his life; compare Matthew 10:23. The phrase, “drink no longer water,” is equivalent to, “drink not water only;” see numerous instances in Wetstein. The Greek word here used does not elsewhere occur in the New Testament. ~Barnes Notes
 
Quoted verse:
Matthew 10:23
But when they persecute you in this city, flee ye into another: for verily I say unto you, Ye shall not have gone over the cities of Israel, till the Son of man be come.
 
Drink no longer water -Though it was commendable in him to keep under his body, as the apostle did, by abstemious living, and not pamper the flesh and encourage the lusts of it, and so preserve purity and chastity; yet it was proper that he should take care of his health, that it was not impaired by too much severity, and so he be incapable of doing the work of the Lord. And it seems by this, that his long and only use of water for his drink had been prejudicial to his health: wherefore the following advice was judged proper: ~John Gill
 
Drink no longer water - as a habit. This injunction to drink wine occasionally is a modification of the preceding “keep thyself pure.” The presbyter and deacon were enjoined to be “not given to wine” (1 Timothy 3:3, 1 Timothy 3:8). Timothy seems to have had a tendency to undue ascetical strictness on this point (see on 1 Timothy 4:8; compare the Nazarene vow, Numbers 6:1-4; John the Baptist, Luke 1:15; Romans 14:1-23). Paul therefore modifies the preceding words, “keep thyself pure,” virtually saying, “Not that I mean to enjoin that kind of purity which consists in asceticism, nay, be no longer a water-drinker,” that is, no longer drink only water, but use a little wine, as much as is needed for thy health. Timothy was of a feeble frame, and prone to timidity in his duties as overseer where vigorous action was needed; hence Paul exhorts him to take all proper means to raise his bodily condition above these infirmities. God hereby commands believers to use all due means for preserving health, and condemns by anticipation the human traditions which among various sects have denied the use of wine to the faithful. ~Jamieson, Fausset, Brown
 
Drink no longer water - Not complete asceticism, but only the need of some wine urged in Timothy’s peculiar physical condition (a sort of medical prescription for this case). ~Robertson's Word Pictures
 
 2] But use a little wine.
 
But use a little wine - The emphasis is on oligōi (a little). ~Robertson's Word Pictures
 
But use a little wine - Mingled with the water - the common method of drinking wine in the East. ~Barnes Notes
 
But use a little wine - some, by "a little wine", understand not the quantity, but the quality of the wine; a thin, small, weak wine, or wine mixed with water; and so the Ethiopic version renders the words, "drink no more simple water", (or water only,) "but mix a little wine"; though rather the quantity is intended, and which is mentioned. Not as though there was any danger of Timothy's running into an excess of drinking; but for the sake of others, lest they should abuse such a direction, to indulge themselves in an excessive way; and chiefly to prevent the scoffs of profane persons; who otherwise would have insinuated that the apostle indulged intemperance and excess: whereas this advice to the use of wine, was not for pleasure, and for the satisfying of the flesh, but for health. ~John Gill
 
 3] For thy stomach's sake.
 
For thy stomach’s sake - It was not for the pleasure to be derived from the use of wine, or because it would produce hilarity or excitement, but solely because it was regarded as necessary for the promotion of health; that is, as a medicine. ~Barnes Notes
 
For thy stomach's sake - to help digestion, and to remove the disorders which might attend it: the Ethiopic version renders it, "for the pain of the liver", and "for thy perpetual disease"; which last might be a pain in his head, arising from the disorder of his stomach. ~John Gill
 
For thy stomach’s sake - Here only in N.T. Our word “stomach.” ~Robertson's Word Pictures
 
 4] And thine often infirmities.
 
And thine often infirmities - weaknesses, lack of strength. ~Robertson's Word Pictures
 
And thine often infirmities - ἀσθενείας astheneias - Weaknesses or sicknesses. The word would include all infirmities of body, but seems to refer here to some attacks of sickness to which Timothy was liable, or to some feebleness of constitution; but beyond this we have no information in regard to the nature of his maladies. In view of this passage, and as a further explanation of it, we may make the following remarks:
 
(1) The use of wine, and of all intoxicating drinks, was solemnly forbidden to the priests under the Mosaic law, when engaged in the performance of their sacred duties; Leviticus 10:9-10. The same was the case among the Egyptian priests. Clarke; compare notes on 1 Timothy 3:3. It is not improbable that the same thing would be regarded as proper among those who ministered in holy things under the Christian dispensation. The natural feeling would be, and not improperly, that a Christian minister should not be less holy than a Jewish priest, and especially when it is remembered that the reason of the Jewish law remained the same - “that ye may put difference between holy and unholy, and clean and unclean.”
 
(2) it is evident from this passage that Timothy usually drank water only, or that, in modern language, he was a “tee-totaller.” He was, evidently, not in the habit of drinking wine, or he could not have been exhorted to do it.
 
(3) he must have been a remarkably temperate youth to have required the authority of an apostle to induce him to drink even a little wine. There are few young men so temperate as to require such an authority to induce them to do it.
 
(4) the exhortation extended only to a very moderate use of wine. It was not to drink it freely; it was not to drink it at the tables of the rich and the great, or in the social circle; it was not even to drink it by itself; it was to use “a little,” mingled with water - for this was the usual method.
 
(5) it was not as a common drink, but the exhortation or command extends only to its use as a medicine. All the use which can be legitimately made of this injunction - whatever conclusion may be drawn from other precepts - is, that it is proper to use a small quantity of wine for medicinal purposes.
 
(6) there are many ministers of the gospel, now, alas! to whom under no circumstances could an apostle apply this exhortation - “Drink no longer water only.” They would ask, with surprise, what he meant? whether he intended it in irony, and for banter - for they need no apostolic command to drink wine. Or if he should address to them the exhortation, “use a little wine,” they could regard it only as a reproof for their usual habit of drinking much. To many, the exhortation would be appropriate, if they ought to use wine at all, only because they are in the habit of using so much that it would be proper to restrain them to a much smaller quantity.
 
(7) this whole passage is one of great value to the cause of temperance. Timothy was undoubtedly in the habit of abstaining wholly from the use of wine. Paul knew this, and he did not reprove him for it. He manifestly favored the general habit, and only asked him to depart in some small degree from it, in order that he might restore and preserve his health. So far, and no further, is it right to apply this language in regard to the use of wine; and the minister who should follow this injunction would be in no danger of disgracing his sacred profession by the debasing and demoralizing sin of intemperance. ~Barnes Notes