Hosea was called by God to live a life that graphically illustrated the spiritual unfaithfulness of Israel, the consequent chastening on Israel, and the forgiving and restoring grace of God. Hosea’s was to marry an unfaithful woman and his children were named Jezreel (God will avenge), Loruhamah (no more loved), and Loaami (not my people).
The time was coming when Israel would face the consequences of their sin. Their sin was breaking their covenant with God, a sin so serious that it was like cheating on your husband or wife. And as a result, God wanted them to know that He would chasten them, abandon them for a time, and disown them for a time.
The beautiful thing about this story is that Hosea would never forsake his wife despite her unfaithfulness. She would go through a time of pain and emptiness because of her sin, but He would love her and bring her back just like God would do with Israel and just as God does with us.
The lesson of Hosea is: 1) sin breaks our fellowship with God and brings all kind of pain, 2) God will chasten those who are unfaithful to Him, but 3) God is gracious and merciful and seeks to restore us back.