Charles Ellicott Commentary John 19:29

"There was set there a vessel full of vinegar: so they put a sponge full of the vinegar upon hyssop, and brought it to his mouth." — John 19:29 (ASV)

Now there was set a vessel full of vinegar.—This vessel of the ordinary sour wine drunk by the Roman soldiers was placed nearby to be given to those who were crucified. Thirst always accompanied death by crucifixion. Furthermore, the mention of the sponge and hyssop makes it probable that the vessel of wine was prepared for this purpose (Compare the note on Matthew 27:48).

And put it upon hyssop.—This detail is unique to St. John. Bochart (Hierozoicon, i. 2, 50) thinks that the plant was marjoram, or a similar plant, and he is supported by ancient tradition. The stalks, about one to one and a half feet high, would have been long enough to reach the cross. This plant is mentioned in one other New Testament passage (Hebrews 9:19) and frequently appears in the Greek Old Testament. The Hebrew word is çzôv, and its identification will always be uncertain because we cannot determine if the Greek translation was based on identifying the plant or on a similarity in the sound of the names.