Not only are they facing an enemy without, they face an enemy within. Jewish lenders are charging contributors an interest rate and having them mortgage there physical holdings against the loan which is a violation of the Mosaic law. To take financial advantage and profit from those attending to God's purpose is an even more debase practice, just as likely to occur today.
We see here that it is proper to pray (even publicly) for the harm of those within that seek to gain personally from those contributing to the causes of God (even by financial usury).
2012 - pBiblx2 Field Wise Bible System Version 2.0.9d - GPL3