Expositor's Bible Commentary Commentary John 7:37

"Now on the last day, the great [day] of the feast, Jesus stood and cried, saying, If any man thirst, let him come unto me and drink." — John 7:37 (ASV)

The climax of the controversy came “on the last and greatest day of the Feast” of Tabernacles. According to the law, the feast was held for seven days, followed by an eighth day of spiritual observance, including an offering to God (on this feast, see comments on Lev 23:33–44). Whether the “last day” was the seventh or the eighth day is not clear. If it refers to the eighth day, it makes the appeal of Jesus in this section all the more meaningful. He took the opportunity to make a public announcement concerning himself and his claims.