Large Catechism: Reflection of the First Commandment (LC I 324-333)

So the First Commandment is to shine and give its splendor to all the others. Therefore, you must let this declaration run through all the commandments. It is like a hoop in a wreath, joining the end to the beginning and holding them all together. Let it be continually repeated and not forgotten, as the Second Commandment says, so that we fear God and do not take His name in vain for cursing, lying, deceiving, and other ways of leading men astray, or trickery. But we make proper and good use of His name by calling upon Him in prayer, praise, and thanksgiving, derived from love and trust according to the First Commandment. In the same way such fear, love, and trust is to drive and force us not to despise His Word, but gladly to learn it, hear it, value it holy, and honor it. (326)