If the cause of action (the injury for which you sued him) arose before he filed BK, your judgment is void. You'll need to consult with an attorney who handles creditor work and decide whether you should file a motion for relief from stay, file a claim in his BK, etc.
I assume that either 1) you did not receive the notice of the debtors bankruptcy filing or 2) the events that led you to file suit against him occured after his filing and that is why you continued to pursue the action against him. If the events that led you to file a suit against him occured prior to the filing of his Ch13, you need to vacate the judgment and see if his case gets dismissed before proceeding with any collection action against him. If his Ch13 gets dismissed you can resume the legal action against him but the judgment would need to be sought again. If he actually receives a discharge then even though you may not have received the notice you obviously know of his bankruptcy and the debt he owes you will be discharged and you will be out of luck. If you attempt to collect on the debt after his discharge, then he will be able to sue you for a discharge injunction violation and I would not want to be you.
If the circumstances which led to your suing him occured after he filed, then you can proceed to try to collect the debt from him, though I would strongly recommend you speak with a creditors side bankruptcy attorney in your area to make sure you can proceed.
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Normally, if a debtor files a Chapter 13, they would have an attorney file a "Suggestion of Bankruptcy" in your civil case against them and that would have prevented your judgment from being granted. If you got notice of the bankruptcy and he, presumably had no counsel in your case against him, then you are at risk of paying penalties for proceeding against a person in bankruptcy and this can include paying his attorney fees. You need to consult an attorney in your area asap, to undue the potential problem before you get a very costly lesson in the powers of the bankruptcy court.