* "When thou hast eaten and art full, then thou shalt bless the LORD thy God..." (Deut. 8:10).
* "And David said to all the congregation, Now bless the LORD your God..." (1 Chron. 29:20).
* "Then the Levites...said, Stand up and bless the LORD..." (Neh. 9:5).
* "I will bless the LORD, who hath given me counsel..." (Ps. 16:7).
* "My foot standeth in an even place: in the congregations will I bless the LORD" (Ps. 26:12).
* "I will bless the LORD at all times: His praise shall continually be in my mouth" (Ps. 34:1).
* "Bless the LORD, O my soul: and all that is within me, bless His holy name" (Ps. 103:1).
* "Bless the LORD, O my soul, and forget not all his benefits" (Ps. 103:2).
* "Bless the LORD, ye His angels...hearkening unto the voice of His Word" (Ps. 103:20).
* "Bless the LORD...His works...His dominion: bless the LORD, O my soul" (Ps. 103:22).
* "Bless the LORD, O my soul. O LORD my God, Thou art very great..." (Ps. 104:1).
* "...we will bless the LORD...for evermore. Praise the LORD" (Ps.115:18).
* "Lift up your hands in the sanctuary, and bless the LORD" (Ps. 134:2).
* "Bless the LORD, O house of Israel: bless the LORD, O house of Aaron" (Ps. 135:19).
* "Bless the LORD, O house of Levi: ye that fear the LORD, bless the LORD" (Ps. 135:20).
Note that all fifteen occurrences are from the Old Testament. Why do you suppose the New Testament does not say we are to "bless the Lord?" It is just a theory, but I believe it is because, in the Old Testament, the major characteristic of God is that He is a God of mercy. In the New Testament, the focus is upon God as being a God of grace! The New Testament writers went out of their way to demonstrate that salvation is not based upon anything we do, but it is based upon what He has done! The New Testament admonition is to THANK THE LORD (Mt. 11:25; Lk.10:21; Jn. 11:41; Rom. 1:8; 7:25; 1 Cor. 1:4; 14:18; Phil. 1:3; 1 Thes. 2:13; 2 Thes. 1:3; 1 Tim. 1:12; 2 Tim. 1:3)!
Israel's focus was to DO things for God; the Church's focus is on what He has DONE!