John 7:37

In the last day. Probably the eighth day, possibly the seventh. The eighth was a day of holy rest added to the seven days of the feast.

If any man thirsteth, let him, etc. Jewish writers say that water was brought every day of the feast in a golden pitcher from the pool of Siloam and poured upon the altar. It is thought that it was when this water was poured out that Jesus cried out, and pointed to the living water.
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