"The Jews then gathered around Him, and were saying to Him, "How long will You keep us in suspense? If You are the Christ, tell us plainly. " Jesus answered them, "I told you, and you do not believe; the works that I do in My Father's name, these testify of Me " (John 10:24-25)
Has it ever struck you that at every turn, the Jews questioned Jesus about being the Messiah? They followed him from place to place to hear him teach and see the miracles he preformed, but always ended up asking him the same thing... "If You are the Christ, tell us plainly."
Throughout the entire scriptures, the proof of the prophet was the fulfillment of the word spoken. For a man to speak forth on behalf of the Lord, the word he spoke must accomplish the purpose to which it was spoken. God said in Isaiah 55:11, "So will My word be which goes forth from My mouth; It will not return to Me empty, without accomplishing what I desire, And without succeeding in the matter for which I sent it. " and again in Jeremiah 1:11, God told Jeremiah, "I am watching over my word to perform it" and lastly in Psalm 138:2, the Psalmist said, "You have magnified Your word according to all Your name. " or as the Amplified Bible says, "You have exalted above all else Your name and Your word and You have magnified Your word above all Your name!" So God places an importance on His word being fulfilled to the point that he watched over it to perform it because His name depends on it.