The appeal of Christ to a vast assembly in the courts of the temple was – ‘If any man thirst, let him come unto me and drink.’ Here are the only two conditions for coming to Christ to receive life, pardon and eternal happiness.
In the last day, that great day of the feast, Jesus stood and cried, saying, If any man thirst, let him come unto me, and drink. He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water. (But this spake he of the Spirit, which they that believe on him should receive: for the Holy Ghost was not yet given; because that Jesus was not yet glorified.) Many of the people therefore, when they heard this saying, said, Of a truth this is the Prophet. Others said, This is the Christ. But some said, Shall Christ come out of Galilee? Hath not the scripture said, That Christ cometh of the seed of David, and out of the town of Bethlehem, where David was? So there was a division among the people because of him.
It’s the last day of the Feast of Tabernacles in Jerusalem. Christ has arrived in the city halfway through the feast and he’s proceeded to the temple and begins to preach. He’s now in one of the outer larger courts of the temple, because to give this tremendous statement he’s obliged to stand, and usually sitting was the position of the teachers of that time.
But now he stands in order to be heard in this vast court and beyond. There were thousands present. This is the third great annual feast of the Jews; it marked the end of the working year. It had picked up some theatre because there was one point in the ceremony that they followed (nothing to do with the feast as God gave it to them, but they’d added to it and so on): the high priest and the retinue of senior priests would go to the pool of Siloam and fill a golden vessel with water, and carry it to the South Gate of the temple and pour it out on the ground as some kind of libation. All the people would cheer. This minor pantomime was very popular, and perhaps that’s what is in mind when Christ utters these particular words. No use following the procedures invented by men that won’t help you spiritually.