What was the law before the mosaic laws? What was the penalty that goes
with sin under that law?
As far as we know, the law given to Israel under Moses was the first
formal covenant between God and a nation or large group of people as a
whole. The time before Moses is sometimes called the patriarchal age,
because from a biblical perspective, this was a time when God worked
through families under a partiarch. Examples are Adam, Noah, Abraham, Job
and Jacob. An interesting case is Jethro, the father-in-law of Moses. In
each case, God communicated his will to a family or tribe through a
patriarch and blessed the group through the obedience and faith of that
partiarch. The Bible does not give a formal description of how this
worked. Nor was there any assurance of salvation for these people, so we
have to infer from what information we have.
The penalty for sin in the patriarchal age was the same that it was under
the covenant given at Sinai, which is the same as it has always been, for
those who know God and for those who do not. As it says in Romans 6:23,
“For the wages of sin is death, but the gift of God is eternal life in
Christ Jesus our Lord.” The penalty for sin was and is spiritual death
and eternal separation from God. Even those who were under the covenant
of Moses are ultimately only saved by the sacrifice of Jesus. As it says
in Revelation 13:8, Jesus is a “Lamb that was slain from the creation of
the world.” Romans 2:5-16 discusses those who sin apart from the law. As
Paul says, “All who sin apart form the law will also perish apart from the
law, and all who sin under the law will be judged by the law.” In the
end, “The righteous will live by faith” (Romans 1:17 and Habbakuk 2:4).
“There is no one righteous, not even one.” (Romans 3:10 and Psalms 14:1).
Whether under the Law of Christ, the Law of Moses or “the law written on
their hearts” (Romans 2:15), the only salvation is through faith in God
and through the blood of Jesus.
Sorry if I got a bit more theological than you intended. I hope this
John Oakes, PhD