No Forgiveness for Monetary Matters:
In the neighborhood of Rav Chaim of Volozhin zt"l, there lived two neighbors, one of whom was very rich and one of whom was very poor. One day, a dybbuk entered the body of the poor man. From then on, he constantly caused the rich man problems. He would yell at him and humiliate him all the time.
Finally, the wealthy man grabbed the poor man and brought him to Rav Chaim. Rav Chaim asked the dybbuk, "Who are you?"
The dybbuk answered, "I was a melamed. I used to teach the children of this rich man's father in their home. One day, the father did a business deal with someone, and he cheated him out of 10,000 rubles. I signed the contract as a witness, even though I knew it was a trick. After I died, the Heavenly court ruled that since I did this, I had to return to the world to repay the debt. Therefore, I am harassing the rich man until he pays it."
When the rich man heard this, he screamed, "You are a liar! I remember you. You were a wicked man who did every aveirah in the Torah. Why should I believe that this is the reason you were sent back to this world?"
The dybbuk replied, "You are right. I did many serious aveiros. But when I got old, I did complete teshuva. In Shomayim, I was told that all my sins had been forgiven, except for this theft, because one cannot do teshuva for monetary matters."
וַיַּרְא אֱלֹקִים אֶת הָאָרֶץ וְהִנֵּה נִשְׁחָתָה כִּי הִשְׁחִית כָּל בָּשָׂר וגו' עַל הָאָרֶץ (ו, יב)
And G-d saw the land and, behold, it was corrupted because all flesh had been corrupted... on the land. (6:12)