"But if ye bite and devour one another, take heed that ye be not consumed one of another." - Gal 5:15
Paul in this passage is not talking about actual flesh and blood eaters amongst the Galatians! He's talking about those who are just as bad though. He's addressing those who devour each other spiritually. He's addressing those who destroy reputations of their fellow brothers and sisters through the terrible sins of backbiting, which includes gossip, slander, and selfishness. He's addressing folks who want to control fellow laborors in the Gospel, including how they speak and articulate the truth. Paul also addressed this behavior in Colossians 3:12-15, by warning the Colossian assembly to stop fighting with each other and instead love each other in thought and deed.
As believers in free and sovereign grace, we should try to avoid having a critical spirit, a spirit of unforgiveness, and divisions amongst ourselves. We need to be uniters, not dividers. We need to be promoters of peace and not strife. And we need to adorn the doctrine of God our Savior in all things (Titus 2:10). We need to stop looking for and finding fault with everything that people say, think, and do. We are laborers in the Gospel and we need to stop directing our energies toward each other and instead spend our time proclaiming the work of our Lord. If all of our time is wasted, and devoted to battling what we perceive to be false religion or "compromisers" or "tolerant" whatevers, then quite simply we are in error and in desperate need of correction.
These days, it seems almost routine to me now that there will always be some zealous, but misguided individuals that arise in and outside of our churches that believe the prime directive of scripture is to go into battle against the trumpeters of the Gospel, whether these trumpeters are dead or alive. They think their primary mission is to destroy the reputation of all those around them, including their neighbors, church members, and actual children of the Lord. These people are divisive, hyper-critical, and spiteful. Indeed, they are heretics. They should be marked as dividers of the brethren and then removed from our churches and avoided (Rom. 16:17, Titus 3:10). With so few believers in this world of unbelief, with all the work that lays ahead of us in preaching the truth, it is shameful that we would allow ourselves to be pulled into a situation where we end up fighting with each other instead of preaching the Gospel and attending to one another's needs. We need to learn to devote our efforts in our struggles against the flesh, mind the two bears, and rest in the knowledge of Christ and Him crucified instead of taking potshots at each other!