In the midst of thunder, lightning and a smoking mountain, the Lord proclaims the 10 Commandments to the Israelites at Mount Sinai. This lesson focuses on the second commandment, which prohibits idolatry. Idolatry was to become a huge problem for the Israelites throughout most of Old Testament history. In the New Testament we see it again as a dominant sin in the Gentile world. In the West, it has continued to be more of a problem than most Christians realize. We also look at one unusual aspect of God’s character: He is a jealous God, who desires our undivided love and devotion.