18 Next, after telling the story of the giving of sight to the man who was blind from his birth, John tarries for a space over the copious discourse to which that incident gave occasion, on the subject of the sheep, and the shepherd, and the door, and the power of laying down His life and taking it again, wherein He gave token of the supreme might of His divinity. Thereafter, he relates how, at the time when the feast of the dedication was being celebrated in Jerusalem, the Jews said to Him, “How long do you make us to doubt?
If you be the Christ, tell us plainly.” And then he reports the sublime words which the Lord uttered when the opportunity thus arose for a discourse. It was on this occasion that He said, “I and my Father are one.” After this, again, he brings before us the raising of Lazarus from the dead: in connection with which miracle the Lord said, “I am the resurrection and the life: he that believes in me, though he were dead, yet shall he live: and whosoever lives and believes in me shall never die.” In these words what do we recognise but the sublimity of the Godhead of Him, in fellowship with whom we shall live for ever?
Once more, John joins Matthew and Mark in what is recorded about Bethany, where the scene took place with the precious ointment which was poured upon His feet and His head by Mary. And then, on to the Lord's passion and resurrection, John keeps by the other three evangelists, but only in so far as his narrative engages itself with the same places.
Source: The Harmony of the Gospels (New Advent)