I’m not catho0lic- but I’ll post something relevant here- The bible states that if we ‘regard iniquity’ (Keep sinning without trying to turn from it with God’s help, ie we keep gossiping, getting angry unjustly, speaking evil of others, sexual sins, steal, whatever those sins may be), God will not hear us- period- We may as well not even pray because God won’t hear us- and our relationship with Him is severely hampered by this-
God is serious about sin- He aint joking- We though dont’ take sin anywhere nearly as serious as we should, and think we are living in a close relationship to God when in reality He doesn’t even hear us when we have unconfessed sin in our lives that we refuse to deal with
We call it mortal sin. You can't do anything of any spiritual worth whatsoever when you're in mortal sin, because the sin --- unresisted and unrepented --- contaminates everything you do and everything it touches.
You can say "But I talk to God!!!!!" when in reality, like the self-satisfied Pharisee in the parable, you're actually just talking to yourself.
Only a mighty act of mercy from God will shake you up so that you can even (1) have the light to *see* and repent that sin, and (2) have the strength to confess it and be joined to Christ's infinite atoning work. "Take up your cross and follow Me."