JHN 7:37

37 [On each of the seven days of the celebration, the high priest poured out some water on the altar in the Temple to remember how God provided water for the people in the desolate area long ago. But the water he poured did not help anyone who was thirsty. So] on the last day of the festival, which was the most important day, Jesus stood up [in the Temple courtyard] and said with a loud voice, “Those who are thirsty should come to me to drink [what I will give them].