““You must not misuse the name of the Lord your God. The Lord will not let you go unpunished if you misuse his name.”
This commandment not only prohibits false oaths and common swearing using Gods name, which is often realized, but it also refers to us to use the name of God in a light or careless manner, without regard to its awful significance. By thoughtless mention of God in trivial conversation, and by the frequent and thoughtless repetition of His name, we dishonor Him. “Holy and reverend is His name.” Psalm 111:9.
This commandment is not just for Hollywood etc though. As Christians, who claim Jesus' name, and take on his name in a world that might only see His character through us - if take his name, but then don't live his life - you are taking His name in vain.
All should meditate upon His majesty, glory, purity and holiness, that the heart may be impressed with a sense of His exalted character; and His holy name should be uttered with reverence.