Adam Clarke on Psalms 89:38

But thou hast cast off - Hitherto the psalmist has spoken of the covenant of God with David and his family, which led them to expect all manner of prosperity, and a perpetuity of the Jewish throne; now he shews what appears to him a failure of the promise, and what he calls in the next verse the making void the covenant of his servant. God cannot lie to David; how is it then that his crown is profaned, that it is cast down to the ground; the land being possessed by strangers, and the twelve tribes in the most disgraceful and oppressive captivity?