If you agree with that statement from Trent you aren’t trusting Christ alone. Salvation conditioned on Christ’s work plus any necessary condition of performance (Rome’s sacraments for instance) stands in stark contrast to the biblical way of salvation. Works and grace absolutely cannot mix. If salvation comes by grace, then it’s not by works. And if it’s by works, then it’s not of grace (see Romans 11). We are saved by grace through the means of faith unto good works (see Ephesians 2:8-10). But it’s never faith that saves, it’s the object of faith—Christ—who saves.
As for the will, God has the only libertarian free will. Man’s will is in bondage to sin due to the Fall. No man will ever willingly choose Christ. No man in his natural state seeks after God. God has to make the man willing first. A man who is truly willing has been regenerated or born again. The New Birth is a miracle, an act of utter grace, performed in the heart by the Holy Spirit.
“We are saved by grace through the means of faith unto good works (see Ephesians 2:8-10). But it’s never faith that saves, it’s the object of faith—Christ—who saves.”
+1
That's not true. I am a member of the Body of Christ. I can say with Paul, "I live --- yet not 'I', but Christ lives in me." In Christ alone I trust.
Final impenitence --- refusal of mercy, refusal of redemption, denial of the Holy Spirit--- is the Sin against the Holy Spirit, which, if unrepented, Christ says is eternal, not forgivable. I trust His words in this, too.
It is the idea of anybody's guaranteed salvation without repentance for sin, which is starkly un-Biblical.