For Sheol see comments on 6.5.

Depart translates the verb “to turn” (see comments on 6.4). Some commentators stress the notion of “returning” here, along the lines of the biblical idea of a person at death returning to the dust from which he was made (104.29). Instead of translating the verb as an indicative shall depart, it may be translated as a wish, “May the wicked depart” (see New Jerusalem Bible, New Jerusalem Bible, Bible en français courant).

The wicked in line a is parallel with the nations (or, “the heathen” in line b). See comments on the nations in 2.1. Line b of verse 17 depends for its meaning on the verb in line a. That is, what happens to the wicked also happens to the nations that forget God. The second line carries the first one further and may be translated, for example, “Wicked people are on their way to death; in fact, everyone who forgets God is headed for death.”

To forget God means to ignore him (New Jerusalem Bible), reject him, not worship him (see also 44.20; 50.22). New English Bible has “are heedless of God.” Cohen defines it thus: “Deliberately ignore His precepts and rebel against His rule.” Forget God tends to mean that people fail to remember God’s name or fail to recognize him. “Reject God” (Good News Translation) is sometimes rendered “they say God is worthless,” or “they say ‘No’ to God,” or “they refuse to obey God.”

Quoted with permission from Bratcher, Robert G. and Reyburn, William D. A Handbook on the Book of Psalms. (UBS Helps for Translators). New York: UBS, 1991. For this and other handbooks for translators see here .