10:5 Samaria. The capital city of the northern kingdom.
calf of Beth-aven. The calf and its priests (2 Kin. 23:5; Zeph. 1:4) were probably not representative of a foreign deity. Rather, they exemplified a highly perverse form of worshiping the Lord in Israel (8:5 note; 13:2 note; 1 Kin. 12:31–33).
mourn. Hosea mocks the pious emotions that the people manifest for an idol.