N.J. Stat. Ann. § 2A:21-2

Each prisoner in a civil action, giving bond to the sheriff, with sufficient sureties, in double the sum for which he is committed, to keep within the prison limits or bounds prescribed by section 2A:21-1 of this title, shall be at liberty to be at large therein. If the sureties in the bond are individuals and not corporate they shall be freeholders of and residents in the county.