The psalmist invites all to bless and praise the Lord. The reasons for his praise are: first, what God has done for him personally (vv. 3-5); second, that he has manifested his justice (v.6) and pardoned his people (vv. 7-12), as a father does his children (vv. 13-18); and, third, he rules everything from heaven (v.19).

The blessing of God contained in this psalm acquires new dimensions in the blessing at the start of the Letter to the Ephesians. There God is praised for filling us with all manner of blessings in Christ (Ephesians 1:2; Psalm 103:3-5), because he redeemed us from our sins through Christ's blood (cf. Ephesians 1:7; Psalm 103:10) and even went so far as to adopt us as his children (Ephesians 1:5).

This psalm arrangement is used in the Mass liturgy on the 7th Sunday in Ordinary Time, Year A.