Matthew 21:16 in the King James Version
And said unto him, Hearest thou what these say? And Jesus saith unto them, Yea; have ye never read, Out of the mouth of babes and sucklings thou hast perfected praise?
Context
15 But when the chief priests and the scribes saw the wonderful things that he did, and the children who were crying in the temple and saying, “Hosanna to the son of David!” they were indignant,
16 and said to him, “Do you hear what these are saying?” Jesus said to them, “Yes. Did you never read, ‘Out of the mouth of children and nursing babies, you have perfected praise’?”
17 He left them and went out of the city to Bethany, and camped there.