Where a church actually follows Scripture, it will manifest - unsaved people will know

that atleast some of the people are for real.  And a few unsaved people will want what the for real people have: a beautiful eternity to look forward, and in the meantime, a life here on earth, where it's okay to be just another everyday working person.  In short, the Lord doesn't scowl people because they drive an old car, with a splotchy paintjob; it's okay to not have a fancy phone / fifty pairs of shoes.

Anyway, a for real group of Christians also attracts attention they don't welcome.  Yep, predators - both corporal and spiritual. And, by the way, if you want to get over on people, the church is a far safer playground, than the smokey barroom - bar people, generally come from places where head-gaming was business-as-usual; so bar people generally know the drill.  In short, peewee-predator running his game there, runs the risk of getting his face punched in.  

Meanwhile, churchpeople who find themselves - or a loved one - defrauded by peewee, will simply keep a polite distance from him (or her) - no fist-fights/broken windshields.  (Talk to sammy - he's not a predator - about the fight he got into over at the bar, a few years back.)

Thing is, like in a nation, there are people who live in a country, and are employed by a hostile nation.  For years, these posers will live and work quietly, will cut their grass, and be the sort of neighbors about anybody wouldn't mind living next door.   Well, there's plants in churches too... not talking about the fern which sits alongside the piano.  See the Book of Jude, it's one page in length; also, II Peter, Chap 3 - less than a page in length.

And here's the thing: the plants tend to be really good actors (and actresses).  There you, for real, are - everyday, it's a struggle for you to mind your temper, your language, your quarrels with Scripture...meanwhile, the plant never seems to have issues - oh, hear him (or her) sing, in a loud, joyful voice - while, the hymn's very words are convicting you, like nobody's business - which actually is a matter between you and the Lord Jesus.  

Btw, that's another earthly benefit of being a Christian.  While the unsaved world has about no issue, whatsoever, nosing into your business, for the Christian, many personal things are between him (or her) and the Lord.  Many things are simply nobody else's beeswax.  Talk to Peter, about the time when Jesus flat out told him, "what's that to you?" - as in, MYOB, bud!