Reaffirming a debt means to go back on the hook for that particular debt.  This is most often seen in the case of the secured creditor being an automobile.  If the debtor wishes to keep an automobile, he or she must enter into a reaffirmation agreement with debt lender.  What this effectively does, is put the debtor and creditor back in the same position that they were in prior to the filing of the bankruptcy.  Thus, the debtor will be responsible for the outstanding debt on that vehicle because they wish to keep that vehicle.  If the debtor falls behind in the future with that vehicle, and the vehicle is repossessed by the creditor, the creditor can seek any auto deficiency amount from the debtor post-bankruptcy filing.  A debtor should be very careful on whether or not he or she reaffirms a debt.  Often times, with a Chapter 7 debtor, the opportunity to surrender the vehicle may be the best option.  It all depends upon whether the debtor can afford or not afford that vehicle once they’ve eliminated all their other miscellaneous debts.
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