Jesus answered, Are there not twelve hours in the day? If any man walk in the day, he stumbleth not, because he seeth the light of this world. Are there not twelve hours in the day? - The Jews, as well as most other nations, divided the day, from sun-rising to sun-setting, into twelve equal parts; but these parts, or hours, were longer or shorter, according to the different seasons of the year. See the note on John 1:39. Our Lord alludes to the case of a traveler, who has to walk the whole day: the day points out the time of life - the night that of death. He has already used the same mode of speech, John 9:4 : I must work the works of him that sent me, while it is day: the night cometh when no man can work. Here he refers to what the apostles had just said - The Jews were but just now going to stone thee. Are there not, said he, twelve hours in the day? I have not traveled these twelve hours yet - my last hour is not yet come; and the Jews, with all their malice and hatred, shall not be able to bring it a moment sooner than God has purposed. I am immortal till my work is done; and this, that I am now going to Bethany to perform, is a part of it. When all is completed, then their hour, and that of the power of darkness, shall commence. See Luke 22:53.
If any man walk in the day, he stumbleth not - A traveler should use the day to walk in, and not the night. During the day he has the sun, the light of this world: he sees his way, and does not stumble: but, if he walk in the night, he stumbleth, because there is no light in it, John 11:10; i.e. there is no sun above the horizon. The words εν αυτῳ, John 11:10, refer not to the man, but to the world, the sun, its light, not being above the horizon. Life is the time to fulfill the will of God, and to prepare for glory. Jesus is the light of the world; he that walks in his Spirit, and by his direction, cannot stumble - cannot fall into sin, nor be surprised by an unexpected death. But he who walks in the night, in the darkness of his own heart, and according to the maxims of this dark world, he stumbles - falls into sin, and at last falls into hell. Reader! do not dream of walking to heaven in the night of thy death. God has given thee the warning: receive it, and begin to live to him, and for eternity.