Are we talking with Jack Chick in Disguise? You do know, Pastor Dave, that Protestantism was BORN from Catholicism. Calling the very thing that gave you your roots the devil is calling yourself the devil.
I assume you aren't Catholic, possibly not Orthodox, because there's this thing... called. Forgiveness. I thought God was Merciful? To forgive is Divine?
So one only is 'sacrificing' their eternal soul if they have no desire to be forgiven of their sins. Your assumption that you do one bad thing and go directly to hell is bonkers.
Well, forgiveness as I understood it was supposed to be insurance for honest oopsies or slip ups or lapses. Like swearing when you drop something on your toe or ignorance of something being a bonafide sin or someone pushing your buttons enough to react. Or it was supposed to fix the past, so to speak. As in before I was saved I yadda yadda yadda, but now I'm forgiven. I think forgiveness to cover willful sinning is not the way it works.
You can willfully sin and be forgiven. At least in catholic faith. Sincere desire for absolution and forgiveness is a requirement, so you may regret taking the action at all (Though not always), but you can gain forgiveness for any action. No matter how bad it is. Why Catholic Priests cannot be used as witnesses if they had a crime confessed to them in the reconciliation room. It's like a 1000x against their religion and would undermine the very concept of reconciliation. Though most Catholic Priests advise, if the crime wouldn't get the death penalty and Justice asks for reasonable punishment, that they accept the prison sentence and turn themselves in.
In Catholic tradition, there are two levels of sin. Venial, which are forgiven at every mass, and Mortal, which can only be forgiven through reconciliation. All sins start as venial, and only become mortal if you understand they are mortal. I was taught Lying is the most basic mortal sin and that goes up to things like genocide.
Its subject must be a grave (or serious) matter. (Though all the ten commandants are serious matters, so lying and cursing with God's name is mortal sinnery, provided the lie is more than a little.)
It must be committed with full knowledge, both of the sin and of the gravity of the offense (no one is considered ignorant of the principles of the moral law, which are inborn as part of human knowledge, but these principles can be misunderstood in a particular context).
It must be committed with deliberate and complete consent, enough for it to have been a personal decision to commit the sin. (Thus, if you rob someone to appease someone holding like, your love, with a gun to her head and you do it, it's only considered Venial.)
Orthodox tradition has a larger list of sins, with Pardonable being the bottom (Pardon as in you don't need penance to gain absolution) to Mortal (Meaning you need LOTS of penance for that absolution) at the top. It's seven long list.