I will sing a new song unto thee, O God - There will be occasion in such a deliverance, or manifestation of mercy, for a new expression of praise. On the phrase, “a new song,” see the notes at Psalms 33:3.
Upon a psaltery, and an instrument of ten strings - The word “and” should not have been inserted here. The idea is, “Upon a lyre or harp (Nebel) of ten strings, will I sing praise.” See the notes at Isaiah 5:12; and notes at Psalms 33:2.