This woman from Samaria found herself
trusting this stranger and said,"Sir, give
me this water, that I thirst not, neither
come hither to draw,"

Here Jesus changed the subject and asked
her to go call her husband. It was not proper
for Him to be talking to a strange woman.
His words forced her to answer that she had
no husband, and He acknowledged her
confession.

Jesus was not omniscience but the gift of the
Word of Knowledge was operating through
Him revealing the truth of her life.
Read John 4:17-18

This convinced her He was a prophet.