This phrase implies that God will come to him in order to save him. The abstract noun "faithfulness" can be translated with an adjective. AT: "My God, who is faithful to his covenant, will come to save me" or "My God will come to save me because he is faithful to his covenant" (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/figs-abstractnouns]])
The abstract noun "desire" can be expressed with the verb "want." AT: "what I want to happen to my enemies" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])
God's protecting the righteous is spoken of as if God were a shield. AT: "our protector" or "the one who protects us like a shield" (See: [[rc://en/ta/man/translate/figs-metonymy]])