Why can't people recognize Christians today?
People cannot recognize Christians today because the concept of separation has been lost. Believers are called to come out from ungodly circumstances, be separate, and live differently—in the world but not of it. When that separation disappears, the world cannot tell a Christian, and Christians cannot tell a Christian.
Les explains that the root issue is a lost concept of separation. The invitation in 2 Corinthians 6:17 is to come out from among that ungodly set of circumstances and be separated. This is not a condition placed on salvation, because under grace God never says “you will or else”; instead He beseeches, and yielding is left up to us. Les warns that this whole matter of separation is being lost sight of even in some more fundamental Bible-teaching and preaching churches. Consequently, the world cannot tell a Christian when it sees one, and Christians cannot tell a Christian when they see one. We are to be different, but that does not mean putting our nose in the air or having no dealings with the world. We are in the world, but we are not to be of it. Paul also writes to the Gentile congregation of Corinth in 1 Corinthians 6:19.