Commentaries
5:17-23 The Divine power of the miracle proved Jesus to be the Son of God, and he declared that he worked with, and like unto his Father, as he saw good. These ancient enemies of Christ understood him, and became more violent, charging him not only with sabbath-breaking, but blasphemy, in calling God his own Father, and making himself equal with God. But all things now, and at the final judgment, are committed to the Son, purposely that all men might honour the Son, as they honour the Father; and every one who does not thus honour the Son, whatever he may think or pretend, does not honour the Father who sent him.
18. God was his Father—literally, "His own [or peculiar] Father," (as in Ro 8:32). The addition is their own, but a very proper one.
making himself equal with God—rightly gathering this to be His meaning, not from the mere words "My Father," but from His claim of right to act as His Father did in the like high sphere, and by the same law of ceaseless activity in that sphere. And as, instead of instantly disclaiming any such meaning—as He must have done if it was false—He positively sets His seal to it in the following verses, merely explaining how consistent such claim was with the prerogatives of His Father, it is beyond all doubt that we have here an assumption of peculiar personal Sonship, or participation in the Father's essential nature.