New Defender's Study Bible Notes
10:4 hemlock. A poisonous plant.
10:6 Jareb. Jareb (“the contentious one”) is probably an epithet applied by Hosea to the Assyrian king Shalmanezer, who resented King Hoshea of Israel because he “brought no present to the king of Assyria” (II Kings 17:4). Therefore, Shalmanezer carried Israel into captivity “for a present” to the contentious king.
10:9 battle in Gibeah. The reference is apparently to the gruesome events described in Judges 20 and 21, with the battle in Gibeah almost resulting in the extinction of the tribe of Benjamin.
10:12 reap in mercy. Compare Hosea 8:7. Sowing the wind is about to reap a whirlwind of judgment in Israel, whereas sowing in righteousness would have reaped mercy. This is apparently a last call to repent and seek the Lord before final judgment.