The church in Pergamos had been infiltrated by false teachers. Jesus commends them for standing strong in the faith in spite of being in the midst of pagan strongholds and temples to dead gods. But a spirit of the Old Testament prophet, Balaam had led some astray. The result was that a doctrine compromised by self-interest instead of God’s interest was loose in the church.
Like Balaam’s she-ass; When God’s word is being compromised we must take a stand and speak-up that we not carry false teachers as they spread their bad doctrine.