The blessedness of God refers to His inexpressible perfection - the sum of all His identifying parts. When the Scriptures state, "Blessed be the Lord." the idea is this: Let God is to be adored and worshiped and praised. Originally, the word "blessed" meant to bow the knees, but it came to be used commonly in the sense of "to worship, adore, and praise." Therefore, to bless God is to exalt Him above all.
1 Peter 1: 3, 4 "Blessed be the God and Father of our Lord Jesus Christ, which according to His abundant mercy hath begotten us again unto a lively hope by the resurrection of Jesus Christ from the dead, to an inheritance incorruptible, and undefiled, and that fadeth not away, reserved in heaven for you."
Col. 2: 9 “For in Him dwelleth all the fullness of the Godhead bodily."
Psalm 103:1-5 Bless the Lord, O my soul; and all that is within me, bless his holy name! Bless the Lord, O my soul, and forget not all his benefits: Who forgives all your iniquities, who heals all your diseases, Who redeems your life from destruction, who crowns you with loving kindness and tender mercies, Who satisfies your mouth with good things, so that your youth is renewed like the eagle’s.