Mortal sin and merits and graces

[In_Jesus_I_Trust]

I understand when a person is in mortal sin that he or she cannot have any graces except forgiveness of sins.
And that his good Works are dead Works.
But what if he was doing all sorts of good works and praying while he was in a state of grace,Will that be forgotten or it Will be given him back when he is in a state of grace again?

 

[Beryllos]

I think of it in terms of our relationship with God. It’s not like a machine with an on/off switch. God loves us at all times, no matter what. The things that preclude our receiving grace are at our end, associated with our imperfect condition.

Here is a concise answer from Catholic Answers (an apologist, not the forum):

Praying While in Mortal Sin

The answer is a qualified “yes.” For example, regarding one’s own sins: When it arises from a love by which God is loved above all else, contrition is called &#...

www.catholic.com

And here is a slightly longer answer from Father Mike Schmitz:

 

[Vico]

I understand when a person is in mortal sin that he or she cannot have any graces except forgiveness of sins.
And that his good Works are dead Works.
But what if he was doing all sorts of good works and praying while he was in a state of grace,Will that be forgotten or it Will be given him back when he is in a state of grace again?

With absolution from mortal sin, condign merit is restored, per general teaching of theologians.

The reconciliation of the sinner with God has as a further consequence the revival of those merits which he had obtained before committing grievous sin. Good works performed in the state of grace deserve a reward from God, but this is forfeited by mortal sin, so that if the sinner should die unforgiven his good deeds avail him nothing. So long as he remains in sin, he is incapable of meriting: even works which are good in themselves are, in his case, worthless: they cannot revive, because they never were alive. But once his sin is cancelled by penance, he regains not only the state of grace but also the entire store of merit which had, before his sin, been placed to his credit.

Hanna, E. (1911). The Sacrament of Penance. In The Catholic Encyclopedia. New York: Robert Appleton Company. http://www.newadvent.org/cathen/11618c.htm