What was the purpose of giving Jesus vinegar to drink ? (Mark 15:23, Matthew 27:34) Some think it was a way to mock Jesus, but others argue that the "vinegar" (with gall) was the diluted wine drunk daily by the Romans, given to alleviate his pain. I would especially be interested to know how the early commentators interpreted this.
In Ps. 69:21 it says,"They gave Me also gall for My meat; and in My thirst they gave Me vinegar to drink."
This is after the Psalmist says in vs 9,"For the zeal of thine house hath eaten Me up; and the reproaches of them that reproached thee are fallen on Me."
Both scenes were witnessed in the life of Jesus: when He drove out the moneychangers out of the Temple (Matt. 21:12/Mark 11:15), and His being offered vinegar; thus fulfilling the Messianic prophecy of David in Ps. 69.
I agree with this previous answer: it is clear that the 'cheap' wine (vinegar) was a mockery designed to extract the last amount of torment: there is little to no alcoholic content in vinegar, there's no 'relief' extracted from it, other than to add to one's sorrow. Significantly, it is recorded that after this He died.
The crucifixion was designed to extract the maximum amount of pain without putting one in shock or stopping vital bodily functions. One typically died of asphyxia-the lungs filling with fluid that one cannot aspirate.
The important truth is contained in Ps. 69:9,"The reproaches of them that reproached thee fell on Me." He bore our reproach "outside the camp" (Heb. 13:13) that we would have "boldness to enter into the holiest by the blood of Jesus" (Heb. 10:19) that we might "obtain mercy and find grace in time of need." (Heb. 4:16)
Mt 27:48, Mk 15:26 - Jesus is offered sour wine on a sponge
These verses are about a different drink of wine than that in question.
Mt 27:34 - The soldiers offer Jesus wine mingled with gall before he is crucified, which He rejects.
A couple of observations before continuing:
1) "Gall" usually means something bitter with an unpleasant taste. It is also used of various poisons. Cf. Job 20:14, Prov 5:4, Lam 3:15, Deut 29:17, etc.
Scofield, Gill, the Pulpit, Matthew Poole, the ESV study Bible, James Edwards, Robert Mounce, and MacArthur say that wine mixed with narcotic/anesthetic agents were commonly given to people being crucified to help with the pain. Myrrh was what was given, which would taste bitter and dull the mind and senses. The Talmud (B. Sanh. 43a) says, "When one is led out to execution, he is given a goblet of wine containing a grain of frankincense, in order to benumb his senses, for it is written, Give strong drink unto him that is ready to perish, and wine unto the bitter in soul." In the words of Alan Cole, "Jesus, however, would not take any such anaesthetic; all his faculties must be unclouded for what lay before him."