How They Should Worship the Lord (vv. 2-4). Both voices and instruments were used in public worship at the sanctuary (see 1 Chron. 25). According to verse 3, the voices were to be enthusiastic (“shout for joy”) in the Spirit but not demonstrative in the flesh, and joyful in the Lord but not jovial and jolly. The instruments should be played with skill and the players give their very best to the Lord. The “new song” may mean new in time or new in expression. The term is used nine times in Scripture (33:3; 40:3; 96:1; 98:1; 144:9; 149:1; Isa. 42:10; Rev. 5:9; 14:3). The Spirit of God can make an old song new to us as we grow in our knowledge of God and His Word, or as we have new experiences, and He can also open our hearts to a song completely new to us. (Some people don’t like to learn new songs.) Our growth in our appreciation of “psalms and hymns and spiritual songs” (Eph. 5:19) is one indication of our development in the Christian life. Of greatest importance is that the worship be scriptural (v. 4a; and see Col. 3:16). A choir has no more right to sing a lie than a preacher has to preach a lie, and not all “religious songs” are doctrinally correct. When God works, He obeys His own Word; so any worship that is contrary to God’s Word will not please the Lord.