"As for a person who stirs up division, after warning him once and then twice, have nothing more to do with him, knowing that such a person is warped and sinful; he is self-condemned."
At best most of us will live on this earth for 75-80 years, which may sound like a lot, but the reality being that it is just a short glimpse in time. Due to that fact alone we must practice the grace of saying NO at times, especially to people.
People are the mission and you should give people time and a hearing on certain issues, but people also waste the one resource that you cannot gain more of, your time. And the truth is that the enemy likes to use divisive people, often believers, to get you distracted from the mission that you have been called to.
I have seen many pastors waste precious time on people who constantly stir up division within the church. A early warning here of those people, it is often the ones that skip from church to church, stirring up division all along. Use the gift of discernment and stay away from those people.
And it is not only pastors, but people in all types of ministry roles that often get distracted by these people as the enemy uses them. Instead of focusing on the true needs at hand we get focused on this individual that is being purely used by the enemy at that moment.
I feel like I learned this lesson in many ways the hard way as I naively didn't expect to experience this by serving in an overseas role as I came in with the mentality of being on the "same team." But I quickly learned and should have realized that the enemy does not like what we are doing over here by punching holes in darkness for King Jesus so of course he is going to use people to get division started.
So my point is practice grace in saying No. This means don't hangout with them, ignore their facebook invites, etc. Practice what Titus 3 tells us in have nothing more to do with them because the reality is that you have more important things, Kingdom work, to be doing and they are being a warped and sinful person.