Qaton Wow Friend, you appear to be protecting Bricks and Mortar.? After all the Lord protects His own with the shield of Faith. Thats how they can walk in this world as strangers. How can love of sinners endanger saints.? Jesus did not come to save the righteous. You are still a sinner....Yes.?
You said 3) Separate the goats away from the sheep when identified by their fruits. 4) Keep God's flock pure and He will walk among us. How do you know which is which, when the Tares are growing amongst the Wheat until the end. If the sinner comes to church, but does not come to Christ for 5 years, - are you going to chuck them out in 4.?
Surely God will keep His flock as "pure" as He requires them to be, in the process of sanctification throughout their lives.? Do you think they might be tainted by sitting in the pew with a sinner.