On the third commandment:
Taking God’s name means more than just speaking it. When a wife marries, she takes her husband’s name, and that involves a whole lot more than saying his name in the wedding vow. She is to be true to him. When you take up the name of Christ as a Christian, you are to be true to Him. All of us break this commandment, even if we never swear, when we break faith with Christ and sin.