For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
The Ten Commandments were part of the Mosaic Law handed to the Israelites in the Torah. Christ fulfilled it for those who believe in Christ.
For if the first covenant had been faultless, there would have been no occasion sought for a second...Behold, the days are coming, says the Lord when I will effect a new covenant..When he said, "A new covenant," He has made the first obsolete. But whatever is becoming obsolete and growing old is ready to disappear.
Hebrews 8:7,8, and 13.
The Ten Commandments were part of the Old Covenant that the New Covenant replaced. That is not to suggest that Christians have no codes of personal conduct in the New Covenant, (New Testament). They are there but failure to do so does not automatically result in death. While condemned for being unrepentant, forgiveness and help is available for the repentant through the Holy Spirit.