Bhagavad Gita, Chapter 9, Verse 30

If even a very wicked person worships Me, with devotion to none else, he should be regarded as good, for he has rightly resolved.

Even someone with a real, troubled past is described here as capable of a real, complete turn.

This doesn't soften or minimize what came before, it states plainly that real, sincere devotion is enough to genuinely count as righteous going forward. Past and present aren't weighed as permanently tied together.