The believers of Islam, Jehovah’s witnesses, Iglesia Ni Cristo and other antichrist groups used to quote John 5:30 in trying to disprove the divinity of Jesus.
[John 5:30] 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.
ANSWER: The answer of the question is in the verse itself. As you can notice in the verse above, there is a reason why Jesus can do nothing, it is because he seeks to please the Father who sent him. Obviously, this doesn’t mean he cannot do anything for he can perform miracles and even raising corpses. What he meant is that all of his works and words are in accordance with the will of the Father. If you want to please your earthly father, you need to heed his advice and do his will, and that’s what Jesus did. You can violate your father’s commandment, but only you chose to follow it in order to please him. Below are verses telling Jesus is doing the will of the Father;
[John 6:38] For I have come down from heaven, not to do My own will, but to do the will of Him who sent Me.
[John 14:10] Do you not believe that I am in the Father and the Father is in me? The words that I say to you I do not speak on my own authority, but the Father who dwells in me does his works.
[John 5:19] So Jesus explained, “I tell you the truth, the Son can do nothing by himself. He does only what he sees the Father doing. Whatever the Father does, the Son also does.
COMMENT: . . . I am in the Father and the Father is in me . . . the Father who dwells in me does his works . . . Whatever the Father does, the Son also does. These statements emphasize that there is oneness of the Father and Jesus. In fact Jesus said that He and the Father are one (John 10:30).
Another reason why Jesus had said he can do nothing was because he exalted or glorified the Father. If you humble yourself to your fellow, it will exalt him. The Father commanded Jesus to glorfy Him (Psalm 50:15), and in return, He will glorify the Son (John 12:28).
Read: The Father and the Son were glorifying each other.
Jesus went to Earth to bring the New Covenant, to build his Church, to speak the words of the Father, to show miracles esp. by healing, to save mankind by perfect obedience of the law, and to set himself as an example how people should live in relation with God. Jesus did all these works in the service of the Father.
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