New Defender's Study Bible Notes
149:1 a new song. “Song” occurs more in the Psalms than in all the rest of the Bible. There are nine “new songs” mentioned in the Bible (Psalms 33:3; 40:3; 96:1; 98:1; 144:9; 149:1; Isaiah 42:10; Revelation 5:9; 14:3). Possibly this new song, sung in the great congregation, is the same as that of Revelation 5:9.
149:3 in the dance. The dancing will express joy and worship, not sensuality.
149:6 two-edged sword. Not only the Scriptures (Hebrews 4:12), but the sword of judgment. The saints will share in the judgment and reign of Christ (I Corinthians 6:2,3; Revelation 2:26,27; 19:4-6).