The prohibition to curse the Name of Most High – this is what was mentioned in 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»? Or is it another commandment?
These two commandments are not the same thing. According the simple meaning of the Scripture, the commandment in the Exodus 20,7 prohibits the perjury using the Name of God. Our Wisemen strengthened the prohibition, to distance a person from dangerous of cursing and swearing using the Name, and they decided to replace the Name of God in usual speech with the Jewish word ha-Shem (His Name).
The prohibition of blasphemy is the prohibition to curse the Name of God.