Albert Barnes Commentary Psalms 139:12

"Even the darkness hideth not from thee, But the night shineth as the day: The darkness and the light are both alike [to thee]." — Psalms 139:12 (ASV)

Yea, the darkness hideth not from thee—Margin, as in Hebrew, “darkeneth not.”

Darkness does not make darkness to you. It makes things dark to us, not to him.

So it is in natural darkness; so in moral darkness. It seems dark to us; it is not so to him.

Things appear dark to us—disappointment, bereavement, trouble, care, losses—but all is light to God. The existence of sin and suffering on the earth seems dark to us; not to him, for he sees the reasons and the end of all.

But the night shineth as the day—one is as bright and clear to him as the other.

The darkness and the light are both alike to thee—Margin, as in Hebrew, “As is the darkness so is the light.”

To you there is no difference. All is light.