Israel had been greatly blessed by the Lord and yet as is the way with fallen man at times when the Lord is blessing us most our heart is far from Him, they had engaged in Baal worship and had even gone far enough as to worship Molech, which involved child sacrifice. They had sent the Lord a message with their actions by showing they would only turn to Him when times where bad, so the Lord promised judgement so they would cry out to Him to save them once more. The Lord makes great promises of deliverence to Israel even going so far as to say He will conquer death but if they would not turn to Him then they would go into exhile. The book of Hosea ends though not with judgement but with a great proclamation of the grace of God and that how if we would turn to Him with our whole hearts then He will shower us with His great mercies.