John 8:34

8:34 Jesus answered them, “I tell you the solemn truth, everyone who practices sin is a slave of sin.

John 8:58

8:58 Jesus said to them, “I tell you the solemn truth, before Abraham came into existence, I am!”

John 10:7

10:7 So Jesus said to them again, “I tell you the solemn truth, I am the door for the sheep.