"By what authority are you doing these things? And who gave you this authority?" (Matt. 21:23)
Jesus was in fact comparing the Jewish priests and elders to the second son. This was because they were presenting to everyone (including God) that they were God's representatives and doing the work of God, when they were actually simply seeking to maintain their authority and superiority in their positions as ecclesiastically-appointed, salaried officials of the temple.
God's representative does not confuse Jesus with the Supreme Being.
God's representative is focused upon pleasing God. This is why Jesus stated:
"By myself I can do nothing; I judge only as I hear, and my judgment is just, for I seek not to please myself but Him who sent me." (John 5:30)Pleasing God has nothing to do with pleasing people. We can see this by Jesus' example. Even though he was accepted as a rabbi by his followers, he was condemned by the ecclesiastical teachers of the Jewish institution. Why? Because he did not teach and do what they wanted.
"For I have come down from heaven not to do my will but to do the will of Him who sent me." (John 6:38)
(For a translation of Jesus' statements from the Gospel of Matthew without institutional sectarian influence, see the Devotional Translation - translated from the original Greek texts.)