Psalms 89:3-5

I have made a covenant with my chosen With David, whom I have chosen to the kingdom. Thy seed will I establish for ever, &c. I will perpetuate the kingdom to thy posterity; which was promised upon condition, and was literally accomplished in Christ, who was of the seed of David. And the heavens shall praise thy wonders That is, the inhabitants of heaven, the holy angels, who clearly discern and constantly adore thy mercy and faithfulness; when men upon earth are filled with doubts and perplexities about it. Thy faithfulness also Understand, shall be praised; (which supplements are usual in Scripture;) in the congregation of the saints Either, 1st, Of thy saints on earth in their public assemblies; who always acknowledge and celebrate thy truth, though they cannot always discern the footsteps of it: or, rather, 2d, Of the angels in heaven, of whom he speaks in the foregoing clause; and who are often called saints, or holy ones.