A.T. Robertson Commentary John 5:30

"I can of myself do nothing: as I hear, I judge: and my judgment is righteous; because I seek not mine own will, but the will of him that sent me." — John 5:30 (ASV)

I (Εγω). The discourse returns to the first person after using "the Son" since verse 19. Here Jesus repeats in the first person the statement made in verse 19 about the Son. In John εμαυτου is used by Jesus 16 times and not at all by Jesus in the Synoptics. It occurs in the Synoptics only in Mt 8:8; Luke 7:7f.

Righteous (δικαια). As all judgements should be. The reason is plain (οτ, because), the guiding principle with the Son being the will of the Father who sent him and made him Judge. Judges often have difficulty in knowing what is law and what is right, but the Son's task as Judge is simple enough, the will of the Father which he knows (verse 20).