The courts have never, ever understood the First Amendment to be absolute and unrestricted. Freedom of the press does not mean that libel must be allowed. You don't have the right to infringe on someone else's rights just because you declare that infringement to be your religious belief.
Saying that "murder is not unconstutional" ignores the requirement of the fifth and fourteenth amendment's statement that nobody can be deprived of life, liberty, or property without due process of law.
“The courts have never, ever understood the First Amendment to be absolute and unrestricted. “
So you believe in a “living constitution”, one that means whatever a particular court decides.
“fifth and fourteenth amendment’s statement that nobody can be deprived of life, liberty, or property without due process of law.”
Those prohibitions apply to the state not private citizens or entities. Criminal laws are the jurisdiction of the states and federal government, and any of them are fine as long as they don’t go against some explicit” right” in the constitution, such as the right to exercise your religion.