God's protection is here referred to as "wings" which a bird uses to cover its' young from danger. "Cover you with his wings" and "under his wings" mean basically the same thing. Alternate translation: "He will keep you safe and protect you" (See: [[rc://en/ta/man/jit/figs-metaphor]] and [[rc://en/ta/man/jit/figs-parallelism]])
God's trustworthiness is here referred to as a "shield" which can protect people who rely on him. The abstract noun "trustworthiness" can be stated as "trust." Alternate translation: "You can trust him to protect you" (See: [[rc://en/ta/man/jit/figs-metaphor]] and [[rc://en/ta/man/jit/figs-abstractnouns]])
No one knows for sure what this word means. Possible meanings are 1) a small shield strapped to the forearm that soldiers used to defend themselves against arrows and swords or 2) a wall of stones set in a circle inside which soldiers could hide and shoot arrows.