Hos 2:13 And I will punish her for the feast days of the Baals when she burned offerings to them and adorned herself with her ring and jewelry, and went after her lovers and forgot me, declares the Lord.
Simply stated, it was Israel’s idol worship that so severely angered God. The first three commandments, written by God’s own hand in a piece of rock, clearly tell us that God is jealous and we are to have no other gods. The third commandment says not to “take the name of YHWH in vain.” This literally means we are not to associate God’s name with false worship or false oaths. Doing these things is blaspheme because man robs God’s name of authority and power and assigns it a place with falsehood. Any time we forget God and chase after the desires of our carnal nature we break these commandments and anger God.