KJV
For it was of the LORD to harden their
hearts, that they should come against Israel in battle, that he might destroy
them utterly, [and] that they might have no favour, but that he might destroy
them, as the LORD commanded Moses.
BSB
For it was of the LORD to harden their hearts to engage Israel in battle, so that they would be set apart for destruction and would receive no mercy, being annihilated as the LORD had commanded Moses.