Jamieson, Fausset and Brown on Jeremiah 23:3-4

3-4. Restoration of Judah from Babylon foretold in language which in its fulness can only apply to the final restoration of both "Judah" and "Israel" (compare Jr 23:6); also "out of all countries," in this verse and Jr 23:8; also, "neither shall they be lacking," that is, none shall be missing or detached from the rest: a prophecy never yet fully accomplished. It holds good also of the spiritual Israel, the elect of both Jews and Gentiles (Mal 3:16, 17; Joh 10:28; 17:12). As to the literal Israel also, see Jr 32:37; Is 54:13; 60:21; Eze 34:11-16.

shepherds ... shall feed them--(Jr 3:15; Eze 34:23-31). Zerubbabel, Ezra, Nehemiah, and the Maccabees were but typical of the consummating fulfilment of these prophecies under Messiah.