We are not under the Law, but we are under obligation to God, who is our Lord and Master. What He tells us will not contradict the ideas of the 10 Commandments.
As Jesus said:
” You have heard that it was said to those of old, You shall not murder; and whoever murders will be liable to judgment. 22 But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, You fool! will be liable to the hell of fire...”