John 7:15-17

7:15 Then the Jewish leaders were astonished and said, “How does this man know so much when he has never had formal instruction?” 7:16 So Jesus replied, “My teaching is not from me, but from the one who sent me. 7:17 If anyone wants to do God’s will, he will know about my teaching, whether it is from God or whether I speak from my own authority.