At the second coming of Christ the angels will be charged with the task of gathering the redeemed (see Matt. 24:31).
My saints.
Heb. chasidim (see Additional Note on Ps. 36). “Amid the tempest of divine judgment, the children of God will have no cause for fear” (PP 341).
Sacrifice.
Heb. zebach, an offering of a slaughtered animal (Gen. 31:54; 46:1; Lev. 3:1; etc.). The ancient Sinaitic covenant was ratified by the sacrifice of oxen and the sprinkling of blood (Ex. 24:5-8; cf. Gen. 15:9-18). The new covenant was ratified by the blood of Christ (Heb. 9:18-23; PP 371). At the coming of Christ the saints who will be gathered are those who have accepted the covenant sealed by the sacrifice of Christ.
Since the English word “sacrifice” also includes the meaning of the surrender of some desirable thing, the words of Ps. 50:5 have at times been employed to encourage self-denial and the dedication of monetary gifts. But the psalmist is not here speaking of monetary gifts. If the text is used in making an appeal for gifts, it should be made plain that the language of the English translation is being accommodated to define an otherwise self-evident truth.