Which is correct?
He repented of his folly.
He repented for his folly.
Keen learner, your threads have nearly identical and unhelpful titles.
Note that Repent would have been a better title as it would have been easier for me to find than 'Preposition' after I'd been away researching it a bit.
They can not be used interchangeably.
This thread explains why much better than I could.