35 Jesus therefore said to them, Yet a little while is the light amongst you. Walk while ye have the light, that darkness may not overtake you. And he who walks in the darkness does not know where he goes. 36 While ye have the light, believe in the light, that ye may become sons of light. Jesus said these things, and going away hid himself from them.
Matthew Henry's Commentary on John 12:35-36
Commentary on John 12:34-36
(Read John 12:34-36)
The people drew false notions from the Scriptures, because they overlooked the prophecies that spoke of Christ's sufferings and death. Our Lord warned them that the light would not long continue with them, and exhorted them to walk in it, before the darkness overtook them. Those who would walk in the light must believe in it, and follow Christ's directions. But those who have not faith, cannot behold what is set forth in Jesus, lifted up on the cross, and must be strangers to its influence as made known by the Holy Spirit; they find a thousand objections to excuse their unbelief.