Pursuant to 11 U.S.C. 362, once a debtor files for bankruptcy, all collection efforts by creditors must cease. Therefore, they can not continue to collect on the filer's debt or property. Keep in mind that secured creditors can file a motion to lift the automatic stay if their collateral is not "adequately protected". The policy behind allowing secured creditors to lif the stay is quite obvious. The debtor would not have any incentive to exercise care of the property, therefore diminishing its value. If the debtor files a Chapter 7, and surrenders the property, then he will not be liable for deficiency. Furthermore, if the automatic stay can not be lifted, then the secured creditor can not take action to retrieve the property. In a Chapter 13, the secured creditor can not lift the automatic stay as long as the creditor is included in the Chapter 13 plan and will be repaid a certain amount. It is also important to note that in a Chapter 7, a co-signer is not protected by the automatic stay while in a Chapter 13 they are as long as the filer stays faithful to his/her Chapter 13 plan.