God the Father will never judge anyone; He won’t condemn the wicked. That role He’s committed to His Son. (Jn 5:22)
To judge Man properly, Christ the Son must be omniscient; He must perfectly know the heart and motive of every action ever committed by anyone, fully understanding everyone’s background, troubles and circumstances. He must know the proper degree of shame and punishment to administer for lifetime’s of sin and rebellion, and He must do this with perfect neutrality and integrity, with perfect justice, with zero bias. This requires Christ to be perfectly and fully divine.
God the Father intends for us all to respect and honor His Son in this role of Judge, in the same way and to the same degree that we honor Himself. (Jn 5:23) There should be no difference in the way we reverence the Father and His Son.
Kiss the Son (Ps 2:12); magnify Him; praise Him; rejoice in Him, serve Him with fear and rejoice with trembling. (Ps 2:11) He came once as the Lamb (Jn 1:36), but He’s coming back to judge as the Lion (Re 5:5), and He will be very, very angry with the wicked. (Re 6:15-17)
If we think carefully about how Christ applied the parable of the two debtors in Luke 18:36-50, we find Him claiming to be the One primarily offended in every transgression, the One principally wronged in every trespass. He’s claiming that all sins are first and foremost against Himself, that He is the Creditor for every moral debt. For anyone but God to think like this is lunacy at best.
Christ cannot merely be a good teacher, for a good teacher would never say anything like this. As others have said so well, Jesus Christ is either a liar, a lunatic, or He is God. There is no in between.