My lips shall greatly rejoice when I sing unto thee,.... Both with vocal and instrumental music; this is praising the Lord with joyful lips, Psa 63:5; and my soul, which thou hast redeemed; signifying that it would not be lip labour, or bodily service, only that he should perform; but that his heart would go along with his lips in praise; and that under a sense of redeeming love, than which nothing can more strongly engage in such work, Psa 103:1. For the redemption of the soul is exceeding precious; being the contrivance of infinite wisdom, the fruit of divine grace, and owing to the blood and sacrifice of Christ.