They so desperately want to trust their works. And if their works fail them, they think they”ll burn off the rest of their sin debt in purgatory. But as it says in Jude, they’ve “gone the way of Cain.” They don’t understand the way of salvation that was made plain from Genesis forward.
Like ethnic Israel of old, “they have a zeal of God, but not according to knowledge. For they being ignorant of God’s righteousness, and going about to establish their own righteousness, have not submitted themselves unto the righteousness of God.” (Romans 10:2-3)
“Salvation is of The Lord.” (Jonah 2:9)
“...born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.” (John 1:13)
“For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast.” (Ephesians 2:8-9)
Catholics have to mis-translate the verse to make a point.