Agency is the notion that choices have consequences.

Repentance is the notion that while experiencing the consequences of my prior choices, I continue to have choices to make, and am not bound to choose as I have heretofore done.

Justice is that if I dig a pit I fall into it.  Repentance is that once in, I can choose to stop digging and even try to clamber my way out.  Mercy is that someone toss me pitons, or even a rope.

Justice is inertia.  Justice does not decree that I suffer certain consequences forever.  It decrees that I suffer those consequences until I or somebody else act to change them.

Momentum exchanges and force and  do not rob inertia.  Mercy and repentance do not rob justice.

The first law of Newtonian spiritics: An agent, once having chosen, will continue to experience the consequences of that choice until acted upon by a new choice, either theirs or someone else’s.

The third law: An agent cannot act to alter the consequences of another’s choice without themselves experiencing the consequences of their action.  Mercy and repentance do not rob justice.  Another name for the third law is atonement.