Psalm 3:3 describes God as a shield, a metaphor also used in Genesis 15:1 where God tells Abram that He is his shield, emphasizing God's protection and defense for His people.
In Psalm 3:4, David cries out to the Lord and is heard, similar to Jonah 2:2 where Jonah calls out to God from the belly of the fish and is heard. Both passages highlight God's responsiveness to the cries of His people.
Psalm 3:5 speaks of lying down and sleeping in peace, which is echoed in Proverbs 3:24, where it is promised that one will lie down and not be afraid, and their sleep will be sweet. Both passages convey trust in God's protection leading to peace.
Psalm 3:6 expresses confidence in not fearing even when surrounded by many enemies, similar to Elisha's assurance to his servant in 2 Kings 6:16, where he says, 'Do not be afraid, for those who are with us are more than those who are with them.'
Psalm 3:8 declares that salvation belongs to the Lord, a theme echoed in Revelation 7:10 where the multitude cries out that salvation belongs to God and the Lamb. Both passages affirm that deliverance and salvation are acts of God.