From the Bible:

Gospel of St. John, first Chapter:

“He was not that light, but was sent to bear witness of that light.” Jesus Christ, by contrast, is described as the light itself. “That was the true light, which lighteth every man that cometh into the world. He was in the world, and the world was made by him, and the world knew him not.”

From the Bhagavad Gita, fourth Chapter:

Unborn, changeless, Lord of Creation and controller of My cosmic nature though I am, yet entering Nature I am dressed in the cosmic garment of My own maya (delusion).

O Bharata, whenever virtue declines and vice predominates, I incarnate on earth. Taking visible form, I come to destroy evil and re-establish virtue.