The Third Commandment

Exodus 20:7 Thou shalt not take the name of the LORD thy God in vain; for the LORD will not hold him guiltless that taketh His name in vain.

Thou shalt not take the name of the LORD thy God in vain: this does not simply mean that the Lord's name is not to be used as an expletive or in the middle of swearing/cussing/cursing, it also includes the conduct of a Christian. As a Christian we take the name of the LORD with us wherever we go and into whatever we engage in. If we claim the name of the LORD, we must embrace all that it is and means.  

God is holy and any use of His name other than reverent use is vain and sin. When an unsaved person sins that is sad enough, but how sad when a Christian offends the Lord and transgresses His law. Far too often the LORD's name is used irreverently and "excused" as being said in innocence, just as a "harmless expression," "not from the heart," or some other reason, when in reality, the Lord's name is only being used as an expression or exclamation of amazement or worse. The above verse also says, "For the LORD will not hold him guiltless that taketh His name in vain."

Matthew 6:9 After this manner therefore pray ye: Our Father which art in heaven, Hallowed be Thy name. In the exemplary prayer we are told that the Lord's name is to be hallowed or highly revered or respected. Thy name - That is, God himself, with all the attributes of his Divine nature - his power, wisdom, justice, mercy, etc. [Adam Clarke]

Acts 4:12 Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved. We call on the name of Lord for salvation and there is salvation in no other.

Philippians 2:9-11 Wherefore God also hath highly exalted Him, and given Him a name which is above every name: That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth; And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father. (Emphasis added)

Psalms 20:7 Some trust in chariots, and some in horses: but we will remember the name of the LORD our God. (Emphasis added)

Proverbs 18:10 The name of the LORD is a strong tower: the righteous runneth into it, and is safe. His name is our refuge. Meditating on the names of Jesus reminds us of His attributes: Counselor, Mighty God, King of kings, Light of the World, Redeemer, Bread of Life, Prince of Peace, Mediator, Good Shepherd, Savior, Immanuel, and the list goes on.

Proverbs 30:7-9 Two things have I required of thee; deny me them not before I die: Remove far from me vanity and lies: give me neither poverty nor riches; feed me with food convenient for me: Lest I be full, and deny thee, and say, Who is the LORD? or lest I be poor, and steal, and take the name of my God in vain. (Emphasis added)