Thou therefore, O Lord God of hosts - God of armies: commanding all the armies of heaven - the angels, and the stars and constellations drawn out in the form of armies; thou, thus endowed with all power, and able to subdue all people though arrayed and combined for purposes of evil - awake to my help. On the meaning of the phrase “God of hosts,” see the notes at Isaiah 1:9.
The God of Israel - The God of the Hebrew people - the descendants of Jacob or Israel - the Protector of thy people - awake to help me, one of those who, being of that covenant people, come under the promise of protection.
Awake to visit all the heathen - On the word here rendered “heathen” - גוים gôyim - see the notes at Psalms 2:1. It is from the use of this word in this verse and in Psalms 59:8, as remarked in the Introduction to the psalm, that DeWette infers that the psalm could not have been composed on the occasion referred to in the title, and argues, that this term could not be applied by David to Saul and his followers. This objection, however, will lose its force if the word is understood as denoting people who had the usual character of pagans, who were fierce, bloody, savage, cruel. In this sense the word might be employed with reference to those who were engaged in seeking the life of David. David, using the common word “heathen” or “nations,” as denoting those who are wicked, cruel, harsh, prays that God would awake to visit them; that is, to visit them for purposes of punishment, or so to visit them as to prevent their carrying out their designs.
Be not merciful to any tricked transgressors - That is, Arrest and punish them “as” transgressors, or “being” transgressors. This prayer is not inconsistent with a desire that such people might be converted, and “thus” obtain mercy; but it is a prayer that God would not suffer them, being wicked people, to go at large and accomplish the work of wickedness which they designed. See General Introduction Section 6. (5) (e).
Selah - A musical pause. See the notes at Psalms 3:2.