John Calvin Commentary Psalms 69:21

"They gave me also gall for my food; And in my thirst they gave me vinegar to drink." — Psalms 69:21 (ASV)

And they put gall into my meat. Here he again repeats that his enemies carry their cruelty towards him to the full extent of their power. He speaks metaphorically when he describes them as mingling gall or poison with his meat, and vinegar with his drink; even as it is said in Jeremiah,

Behold, I will feed them, even this people, with wormwood,
and give them water of gall to drink (Jeremiah 9:15).

But still the Apostle John justly declares that this Scripture was fulfilled when the soldiers gave Christ vinegar to drink on the cross (John 19:28–30); for it was necessary that whatever cruelty the reprobate inflict on the members of Christ should be represented by a visible sign in Christ himself.

We have stated on the same principle, in our remarks on Psalm 22:18, that when the soldiers parted the garments of Christ among them, that verse was appropriately quoted, They parted my garments among them, and upon my vesture did they cast lots; although David’s object was to express by figurative language that he was robbed, and that all his goods were violently taken from him and plundered by his enemies.

The natural sense must, however, be retained; which is, that the holy prophet received no relief, and that he was in a condition similar to that of a man who, already greatly afflicted, found, as an additional aggravation of his distress, that his meat was poisoned, and his drink rendered nauseous by the bitter ingredients with which it had been mingled.