Blessed be the Lord! For he has heard the voice of my pleas for mercy. The Lord is my strength and my shield; in him my heart trusts, and I am helped; my heart exults, and with my song I give thanks to him. -Psalm 28:6–7
To bless the Lord is to adore or to praise him. Why? Because he heard and answered David’s pleas for mercy. Moreover, he hears our as well (1 John 2:14 cf. James 5:16-18). Because we know Christ is the Lord of all the cosmos and that he hears our prayers, we too can posses David’s same unshakeable confidence in him whom our hearts trust. While the unbelievers leverage power, technology, and wealth to garner strength and security in this life, the Lord is our strength and shield. For this our hearts exult and with songs of praise we give thanks to him.
Rejoice in the Lord always; again I will say, rejoice. Let your reasonableness be known to everyone. The Lord is at hand; do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus. – Philippians 4:4–7