Jamieson, Fausset and Brown on Micah 5:8

8. as a lion--In Mi 5:7 Israel's benignant influence on the nations is described; but here her vengeance on the godless hosts who assail her (Is 66:15, 16, 19, 24; Zec 12:3, 6, 8, 9; 14:17, 18). Judah will be "as as lion," not in respect to its cruelty, but in its power of striking terror into all opponents. Under the Maccabees, the Jews acquired Idumea, Samaria, and parts of the territory of Ammon and Moab [Grotius]. But this was only the earnest of their future glory on their coming restoration.