Knew not that it was Jesus - Probably it was yet twilight, and in the distance they could not distinctly recognize him.

Knew not that it was Jesus - Probably because it was either not light enough, or he was at too great a distance, or he had assumed another form, as in Mark 16:12; otherwise his person was so remarkable that all his disciples readily knew him when he was at hand: see John 21:12.

But when the morning was now come,.... The day began to dawn, and light to appear, very early in the morning; for Christ visits his right early, and is a present help to them in their time of trouble.
Jesus stood on the shore: on firm ground, whilst his disciples were beating about in the waves, and toiling to no purpose. So Christ, risen from the dead, is glorified, is in heaven; but not unmindful of his people amidst all their afflictions in this world:
but the disciples knew not that it was Jesus; though he was so near them that they could hear what he said; but it not being broad daylight they could not distinctly discern him, or their eyes might be held that they could not know him. So Christ is sometimes near his people, and they know it not.

Jesus stood--(Compare John 20:19, John 20:26).
but the disciples knew not it was Jesus--Perhaps there had been some considerable interval since the last manifestation, and having agreed to betake themselves to their secular employment, they would be unprepared to expect Him.

When the morning was now come. The Revision is correct: "When the day was now breaking."

They knew not that it was Jesus - Probably their eyes were holden.