our ... their--change of person. Micah in the first case identifying himself and his sins with his people and their sins; in the second, speaking of them and their sins.
20. perform the truth--the faithful promise.
to Jacob ... Abraham--Thou shalt make good to their posterity the promise made to the patriarchs. God's promises are called "mercy," because they flow slowly from grace; "truth," because they will be surely performed ([Lu 1:72], 73; [1Th 5:24]).
sworn unto our fathers--([Psa 105:9], ). The promise to Abraham is in [Ge 12:2]; to Isaac, in [Ge 26:24]; to Jacob, in [Ge 28:13]. This unchangeable promise implied an engagement that the seed of the patriarchs should never perish, and should be restored to their inheritance as often as they turned wholly to God ([De 30:1], 2).