I must work the works of him that sent me, while it is day. — The better reading is probably that which has we, instead of “I,” and perhaps also that which has us, instead of “me”; but this latter change is not so well supported by MS. authority. The clause would read then, We must work the works of Him that sent Me (or us) while it is day. He identifies the disciples with Himself in the redemptive work of His mission. There is before them a striking instance of the power of evil. He and they are there to manifest the power of good. They must gird themselves to the task. If we are right in placing the whole section from John 7:37 to John 10:21 on the same great day of the Feast (comp. Note on John 9:14), then this work must have come near the close of the day. The sun sinking to the west may have reminded them that the day was passing away, and that the night was approaching. He was reminded of the day of life, and the night of death. He will not be long in the world (John 9:5). That night will be the close of His human work, and the shadows of evening are already falling upon Him.
The night cometh, when no man can work. — He does not except even Himself from the proverbial law. The day of opportunity passes, never to return. His own great work of doing the work of Him that sent Him, could only be done when that day was present. It has, of course, been ever done in the work of His church under the guidance of His Spirit; but the work of His own human activity on earth ceased when the night came. Comp. John 11:9 for this thought of the hours of the day.