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?
But thou hast cast off - literally, Thou hast treated as a foul, offensive thing; thou hast treated him to whom these promises were made, as if he were a vile and detestable object - as that which one throws away because it is worthless or offensive.
With thine anointed - With him who had been anointed as king - anointed as thine own - to administer justice, and to rule for thee. 1 Samuel 16:1, 1 Samuel 16:13. This might seem to refer to the time of Absalom, when David was driven from his throne and his kingdom; see, however, the Introduction to the Psalm.