Romans 3:31 Do we then make void the law through faith? God forbid: yea, we establish the law.
This verse of scripture is confusing because of the general understanding of establish which in modern terms means; set up (an organization, system, or set of rules) on a firm or permanent basis. God has already done that so reusing that definition becomes redundant. Man cannot make the laws that God has already established, in the modern sense.
We have to once again look to the Greek with its multifaceted definitions to see which tense this word applies in context.
Histemi in its third tense means to set or place in a balance; to weigh: money to one (because in very early times before the introduction of coinage, the metals used to be weighed)
The law was heavily weighted towards punishment. Death was required for all violations against God. There were lesser penalties for wrongs done against another person, but punishment was the primary focus.
There was no way to bring law into balance, nothing that could balance the heavy weight of death. There was nothing that created life to offset the weight of sinning against God.
John 3:3,7 Jesus answered and said unto him, Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God. Marvel not that I said unto thee, Ye must be born again.
Only being born again establishes life on the other side of the scales of justice. God, being a just God, had to create a just answer to a just law that could bring the law back into balance.
Ephesians 2:8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
Law without grace is out of balance and there is no justice. Paul’s establishment is bringing balance to the law by preaching grace, a way to get on the right side of the scales of justice by being born again.