It is an essential difference between man's thoughts and God's, that man who makes himself the center would have light, as he says, even divine light, to have life. God's way is all the opposite: “The life was the light of men.” Life, the Person of the Lord Jesus, comes first; and that is right, because it, and it alone, puts God in His place. Nor could the law do this; it was given to man as man.
As man was made in the image of God after His likeness, so Christ was in nature the light of men (not of angels as such): He is the image of the invisible God. But we are born of God, and “he that hath the Son hath life,” God having given to us eternal life—quite a different thing from simply being immortal. It is the possession of that divine life, which in Christ never had a beginning, that eternal life which was with the Father, and was manifested to us, and of which in its moral qualities it is said, “which thing is true in Him and in you, because the darkness is passing and the true light already shineth.” Hence it is said of us, “Ye were sometimes darkness, but now are ye light in the Lord.” But even this partaking of the divine life or nature is dependent as it is derivative. And though it is a nature which in itself does not sin and delights in God, as the eye in light, yet we have to walk in the light. We have fellowship with the Father and with His Son Jesus Christ in that life which is from them (and that through the Holy Ghost). But then God is light, and fellowship with Him out of the light is impossible.
It is not, If we walk according to the light. This is the practical consequence in the world, even when we are not directly enjoying communion; but we walk in the light, when we walk with God fully revealed to soul and conscience. It is a real thing in life: we walk, but more than walking according to light. It is a walking in the presence of a fully revealed God, the conscience and spiritual judgment and apprehension being in the light as He is: what God is perfectly seen, and everything by it, and all clear as it is in light and for the soul. If we walk thus with God inwardly, all is judged inwardly; and our life is only the expression of the working of God in power in the life which we have of Him, of Christ in us (wisdom and power). J.N.D.