Sufficiency of Scripture

These things Jesus spoke, and He went away and hid Himself from them.  But though He had performed so many signs before them, yet they were not believing in Him. This was to fulfill the word of Isaiah the prophet which he spoke: “Lord, who has believed our report? And to whom has the arm of the Lord been revealed?”  For this reason they could not believe, for Isaiah said again,  “He has blinded their eyes and He hardened their heart, so that they would not see with their eyes and perceive with their heart, and be converted and I heal them.” These things Isaiah said because he saw His glory, and he spoke of Him.  Nevertheless many even of the rulers believed in Him, but because of the Pharisees they were not confessing Him, for fear that they would be put out of the synagogue; for they loved the approval of men rather than the approval of God.

John 12:36-43