1. Exodus 20:7 prohibits taking the name of the Lord in vain, essentially forbidding the misuse or disrespect of God's name. It states, "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".
2. Question is, is Jesus both Lord and God?
Then he said to Thomas, “Put your finger here; see my hands. Reach out your hand and put it into my side. Stop doubting and believe.” Thomas said to him, “My Lord and my God!” - John 20:27-28.