—John 12:47-50 (NASB)
When we read the biographies of famous historical figures, it's generally a documentation of influences. What kind of family did they grow up in? Where did they go to school? Who were their mentors? It's a documented stream of factors like these that produces a logical list of how that person came to think and act like they did during the opportunities that made them famous. The closest we come to acknowledging a greater power at work in these people's lives is by mysteriously invoking the words "fate" or "kharma" or perhaps "chance coincidence", all of which actually belies our belief that the person was really just in the right place at the right time to take advantage of the opportunities in the right way to become famous. Jesus repeatedly challenges us to test every word and action of HIS life against whether or not it is of God.
Jesus leaves absolutely no wiggle room; either it's 100% legitimately from God or He's a fraud. He makes the bold claim that His words are not His own but that God "has given Me a commandment as to what to say and what to speak." Jesus provides the condition that you can't simply label His words as teaching or philosophy or interesting thoughts. We are forced to either accept them or reject them, and in the process knowing that we are accepting or rejecting God the Father that sent Him.
To be sure, there is definite application here for unbelievers accepting or rejecting His Word, and therefore experiencing salvation. (Or not.) But for believers, don't we have an even greater responsibility to embrace ALL His Word? Can we be selectively obedient to MOST of His Word, not ALL of it? Our obedience to His entire Word is a direct reflection of our witness and testimony of whether we accept God fully, or reject Him, even in part. It will come back to testify about the quality of our faith.†††