A quick read of Luke’s account of the preaching of John the Baptist shows up noticeable similarities to the account in Matthew (most likely from the common source Q). Luke and Matthew share the reference to the brood of vipers, the warning to flee from the wrath to come, language about bearing fruit worthy of repentance, the ax at the root of the tree, and the reference to the mightier one who is coming who baptizes in spirit and fire (judgment and power). But there are also remarkable differences. In Luke, the brood of vipers comment is addressed to all the people, not just Pharisees.