Matthew 5:22

22 But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.

In Matthew 5, Jesus says that anyone who calls another a fool is in danger of going to Hell. Despite this, Jesus calls people fools in Matthew 23, putting himself in danger of the very Hell fire he warned us about in.

Matthew 23:17

17 Ye fools and blind: for whether is greater, the gold, or the temple that sanctifieth the gold?

Furthermore, God also calls people fools in Luke 12.

Luke 12:20

20 But God said unto him, Thou fool, this night thy soul shall be required of thee: then whose shall those things be, which thou hast provided?

Both the father and the son have placed themselves in danger of going to Hell. That, or the son lied when he claimed that calling another a fool had this effect. Either way, this proves that Jesus was not without sin.

One might be able to make the claim that the danger of Hell isn’t the same as actually going to Hell. Perhaps Jesus was merely warning against behavior that might lead to rancor. Either way, I can’t think of anyone more deserving of eternal damnation than the guy who invented it.