If he used the gas card or the bank card you can report either or both as stolen.
If he used them, or attempts to, he can be prosecuted. He can go to jail.
If he bought something in his name and stops paying for it, they may be able to come after you for the debt depending on State Law and how that State views property ownership after people are married. You need to talk to an attorney and get this stuff figured out and straightened out.
If he bought something (like the 4 wheeler) and stops paying for it, do NOT pay anything and let it be re-po'd. If his credit is ruined, that is a consequence of his actions.