Can anyone explain to me how these work in relation to salvation? Its a subject I’ve always found myself ignorant of.
The general meaning of the word “grace” is an unmerited gift. In connection with salvation however, Catholics are referring to a very specific grace - sanctifying grace.
We are saved by grace alone.
We receive this saving grace (sanctifying grace) through faith and baptism.
To retain this saving grace we must be obedient (do or not do what Our Lord has commanded.
If we commit a mortal/serious sin with full knowledge and consent, we lose the supernatural life of grace in our souls.
If we repent and confess the sin, the life of grace is restored to our souls.
To enter heaven, we must be in the state of sanctifying grace at the time of death. (In other words, not be guilty of unrepented serious sins.)
[There are many passages which show that we can lose the grace of salvation after initially receiving it. Here are just a few:
Parable of the seed Mt. 13:18-21.
1 Cor 9:27; Gal 4:8,9,11; Gal 5:4, 19-21; 2 Tim 4:4; Heb 2:1; 2 Peter 2:20; 2 Peter 3:17. (All of these are being written to baptized - saved - Christians)]
The following is the definition given for sanctifying grace in the Glossary of the Catechism of the Catholic Church:
SANCTIFYING GRACE: The grace which heals our human nature wounded by sin by giving us a share in the divine life of the Trinity. It is a habitual, supernatural gift which continues the work of sanctifying us–of making us “perfect,” holy, and Christlike.
Here are three articles that may help you:
Grace:What It is and What It Does
Laudatur Iesus Christus.
I hope this is a helpful place to start:
“(Sanctifying) Grace” is the life of God. God loves God; that is His life, the basis of being, of all life, and the only eternal reality.
“The New Covenant” is the means and instructions given to us by God which allow us to participate in His life, so that we might have abundant and eternal life.
“Faith” is our doing what God has instructed, trusting that it will work, even though we, because of our limitations of foresight and knowledge, cannot judge for ourselves that it will be good for us.
“Salvation” is success in participating in the Divine life, both in this life and eternally.
“Damnation” is continuing to exist after this life, having failed to gain eternal life – therefore damnation is a form of eternal death, personal existence without life.
Spiritus Sapientiae nobiscum.