Recently, a member texted me the simply question, "Hosea 1:2, why?" Basically, he wondered why God called the prophet Hosea not only to marry a prostitute, Gomer, but a woman whom he knew would be unfaithful to him. It's a great question since understanding the answer unlocks both the book of Hosea and the gospel of grace in Christ.
A prophetic picture
Essentially, God called Hosea to act out a prophetic picture. Just as Hosea showed compassion by marrying the prostitute, Gomer, so the Lord had mercifully chosen Israel from among among the nations. He took them for his Bride, so to speak, despite their having been spiritual whores, worshipping many gods. The covenant made with them at Sinai was a kind of wedding between God and the people.
After receiving such compassion and intimacy, you might expect them to respond with gratitude and faithfulness. Instead, almost immediately after being rescued from Egypt, they began cheating on the Lord with idols. Similarly, God called Hosea to marry a woman whom he knew in advance would betray him. Yet for all this, Hosea was told to forgive and eventually live with her in love. In this way, the Lord prophesied his undying faithfulness and love toward wayward Israel.
The pain and dishonor which Hosea experienced throughout this ordeal helps you to empathize with the long-suffering grief and shame which God endures whenever we turn our affections away from him to sin and unbelief. In a word, this unique book leads Christ’s Church to value her husband. We learn return from idolatry into his loving, forgiving embrace.