Satan himself quoted scripture in the temptation of Christ, though it was misquoted, He is still very much active in the churches today..and is the first one in the door! It’s an easy thing to call ones self a Christian...heck muslims are doing so as refugees in order to remain in their host countries.
But it is quite another thing to ‘show’ one is a Christian....sadly today it’s not uncommon you cannot tell the difference.