The cure of all shame and insecurity is believing God fully accepts you in the Gospel - just as you are right now - and realizing He will never change His mind.
I mean to deal more broadly and deeply here with the problem I raised in the previous post. Let me start by making it clear that I do not believe obedience/works of faith are actually at odds with grace in Christian theology. What I mean by "performance vs. grace" is that this is how many Christians sometimes see their experience of faith. Sometimes they feel that they can never measure up to a standard of holiness and perfection, and therefore get depressed and discouraged by shame, or they feel that all the teachings of grace and forgiveness don't fit with the commands to do good works and to be holy. This leads to a creeping insecurity that we really aren't fully accepted by God unless we 'complete' our faith by getting really good at obedience. That's what Jerry Bridges calls "the performance trap."
I know of no better or more encouraging antidote to this trap than The Discipline of Grace, which Bridges wrote to help Christians who want to accept the free grace of God, but feel burdened by their inability to meet our expectations of Christian behavior and holiness. If you've been weighed down by this burden as I have, I hope a very short unpacking of his solution will convince you to get this book and savor it. It is endlessly encouraging.
First, Bridges identifies the problem with the performance trap: Christians accept that we are saved and forgiven only by faith in Christ, and "readily acknowledge that we can never through our own obedience attain a righteousness that is sufficient for salvation. But then as believers we act as if we can live lives acceptable to God." In short, "we know God's blessings come to us through Christ, but we also have this vague but very real notion that they are also conditioned on our behavior." The trap is that we have separated 'salvation in Christ' from 'acceptance by God.' We have fallen into a misguided feeling that, although Christ fully and finally saved us from our sins and purchased our eternal life, we aren't completely acceptable to God or approved by God unless we perform well.