Is it permissible to marry a man who took out a usurious loan to buy a house and cover his study expenses, with the intention of helping him repent after marriage?

There is no blame upon you for marrying this man. Indeed, it is advisable if you predominantly believe that he committed what he did out of ignorance or misconception, or that he is not persistent in these actions and will accept advice and repent. It is not a condition for his repentance to dispose of a house acquired through a usurious loan. However, if you predominantly believe that he is persistent in usury and indifferent, then it is not advisable to marry him.