When the body attacks itself as it does with arthritus and other diseases, it's called an auto-immune disease. It does damage to its own body as if it were an enemy. I don't know why this happens. It is senseless and self-defeating.
I see this within the body of Christ. What makes a member of the body of Christ attack another member? The whole body suffers including the clueless member who causes it all.
It's so hard knowing how to deal with this. I know that Jesus says to forgive and to pray for our enemies. He loves the one lamb who has wandered away from the ninety-nine. Indeed, there have been times that I wandered and I am thankful to the good Shepherd for coming after me.
I've heard it said that when there is a wayward lamb that continually wanders and by example teaches the other sheep to follow suit, that the shepherd will break that lamb's legs and then carry it on his shoulders until it is mended. The lamb's heart is knit to the shepherd's heart by then.
I know one thing: to turn against the body is seriously divisive and injurious, but to then turn and attack the attacker will only compound the damage.
Dear Jesus, give me that love that knows no limits for the attacker of the body. It is impossible in my humaness to love someone like that, but Your love is extravagant and endless. I end with Ephesians 4:1-6: "I...entreat you to walk in a manner worthy of the calling with which you have been called, with all humility and gentleness, with patience, showing forbearance to one another in love, being diligent to preserve the unity of the Spirit in the bond of peace. There is one body and one Spirit, just as also you were called in one hope of your calling; one Lord, one faith, one baptism, one God and Father of all who is over all and through all and in all."