"A division necessary"
"And God saw the light, that it was good: and God divided the light from the darkness"
Light might well be good since it sprang from that fiat of goodness, "Let there be light".
We who enjoy it should be more grateful for it than we are, and see more of God in it and by it. Light physical is said by Solomon to be sweet, but gospel light is infinitely more precious, for it reveals eternal things, and ministers to our immortal natures. When the Holy Spirit gives us spiritual light, and opens our eyes to behold the glory of God in the face of Jesus Christ, we behold sin in its true colours, and ourselves in our real position; we see the Most Holy God as he reveals himself, the plan of mercy as he propounds it, and the world to come as the Word describes it. Spiritual light has many beams and prismatic colours, but whether they be knowledge, joy, holiness, or life, all are divinely good. If the light received be thus good, what must the essential light be, and how glorious must be the place where he reveals himself. O Lord, since light is so good, give us more of it, and more of thyself, the true light.
No sooner is there a good thing in the world, than a division is necessary. Light and darkness have no communion; God has divided them, let us not confound them. Sons of light must not have fellowship with deeds, doctrines, or deceits of darkness. The children of the day must be sober, honest, and bold in their Lord's work, leaving the works of darkness to those who shall dwell in it for ever. Our Churches should by discipline divide the light from the darkness, and we should by our distinct separation from the world do the same. In judgment, in action, in hearing, in teaching, in association, we must discern between the precious and the vile, and maintain the great distinction which the Lord made upon the world's first day. O Lord Jesus, be thou our light throughout the whole of this day, for thy light is the light of men.
C. H. Spurgeon