Charles Ellicott Commentary Psalms 13:3

"Consider [and] answer me, O Jehovah my God: Lighten mine eyes, lest I sleep the [sleep of] death;" — Psalms 13:3 (ASV)

Lighten. —Literally, give light to my eyes that I may not go to sleep in death, that is, go to sleep and never wake; “sleep unto death,” as the Septuagint (Compare Psalm 6:5 for the nature of the fear; and for the form of expression, 1 Samuel 14:27, 29).