Hosea is the first book of the twelve minor prophets. Because the times are outwardly prosperous, idolatry prevails and immorality is rampant. Hosea urges a return to God in order that He may show mercy and forgiveness.

Hosea 6

6:10 I have seen an horrible thing in the house of Israel: there is the whoredom of Ephraim, Israel is defiled.