The First Commandment instructs our heart toward God. This commandment guides our lips. Using God's name to cover up lies or spread falsehood is a great evil and sin, and it happens in many ways in life. There is no greater sin against the Second Commandment than using God's name to preach, teach, and spread false doctrine. Luther explains how to use God's name properly and how to take an oath without sin. By faith, our hearts and our mouths honor God by confessing Him and His Word purely. Luther recommends beginning and ending each day, and each meal, by making the sign of the cross and commending ourselves to God. Making the sign of the cross is not a "Roman Catholic" practice, but has its roots in the earliest years of the Church. It is a visible way to remind ourselves whose we are through our baptisms and how we have been redeemed by the cross of Jesus Christ.