35 So Jesus said to them, “For a little while longer the Light is among you. Walk while you have the Light, so that darkness will not overtake you; he who walks in the darkness does not know where he goes. 36 While you have the Light, believe in the Light, so that you may become sons of Light.” These things Jesus spoke, and He went away and hid Himself from them. 37 But though He had performed so many signs before them, yet they were not believing in Him. 38 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?” 39 For this reason they could not believe, for Isaiah said again, 40 “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.” John 12:35-40 (NASB)
God does control all things. If you doubt it, read the following passage from Isaiah.