John 1:25

And they asked him, saying, "Why then do you baptize if you are not the Christ, nor Elijah, nor the Prophet?"

Surrounding context

1:24 Now those who were sent were from the Pharisees.

1:25 And they asked him, saying, "Why then do you baptize if you are not the Christ, nor Elijah, nor the Prophet?"

1:26 John answered them, saying, "I baptize with water, but there stands One among you whom you do not know.