This question came in my email today, and I am going to answer it here:
Question Detail: Can I rent my house to someone in need if I filed bankruptcy and the case has been discharged for 3 years but bank has done nothing yet with the house?
Answer: Yes, but you should have a plan for if the bank does come for the house.
The fact is that even though you have filed bankruptcy, discharged the mortgage and advised the court and Trustee of your intention to surrender the property, it is still yours until the bank comes to take it away. It is not uncommon for the bank to take three years to come for a house. Unless and until it does, you still own it and may treat it as your property. If you live in it, you may continue to live in it until the bank forecloses upon it and evicts you (or pays you to move out). If it is a rental property, you may continue to collect rent until the bank forecloses.
I will admit that I am a little uncomfortable with renting out a property to a new tenant. The concern is that the bank will foreclose during the lease. Here in Massachusetts, such a tenant would have rights against the bank, so no will injustice is likely to result. Just keep in mind that there are scenarios here in which you could be rightly accused of engaging in a unfair and deceptive business practice. That it has been three years bothers me, because that is commonly around the time banks get around to foreclosing (do not ask me why because I have no idea). You probably should speak with a lawyer about this specific transaction.