Many are in reality fighting his battles while they profess to serve under the banner of Christ. These traitors in the camp may not be suspected, but they are doing their work to create unbelief, discord, and strife. Such are the most dangerous of foes. While they insinuate themselves into our favor, and gain our confidence and sympathy, they are busy suggesting doubts and creating suspicion. They work in the same manner as did Satan in heaven when he deceived the angels by his artful representations, placing darkness for light, and making the forbearance and mercy of God to appear as harshness and severity. As he worked at the beginning, so he works in the end, only concealing himself more perfectly from view.... (OHC 360.4) MC VC