"For such are deceitful workers, transforming themselves into ministers of Christ. And no wonder, for Satan himself transforms himself into an angel of light. So it is no wonder if his ministers also transform themselves into ministers of righteousness. But their end shall be according to their works."So how do we know the difference,if they imitate us?Well ,2 things I personally think are a "giveaway" are:I've heard this many times, they preach a message that's somewhat "off" the actual Gospel message,but say that theirs is the "real" gospel message, and for years, soon after Jesus went back to heaven, the Gospel as we know it is "wrong",and all the "other " churches nowadays,they're the ones "following Satan,and the pastor says, THEIR church is the" only true church", who God raised up in the last days,to give the "right" Gospel.And they say,"Don't listen to the "other" churches. only listen to "my" church!!Another thing I think is a giveaway is,{along with thinking they found"the" church}is I 've heard them say,they don't want to "share" things about their beliefs with those "outside" their belief system.But wait!!What did Jesus actually say?"Go out and preach the Gospel to every nation, Those who believe and are baptized will be saved. Those who don't will be damned."GO OUT AND PREACH THE GOSPEL TO EVERY NATION.A little different from not wanting to talk to the "unwashed" like these groups.SOOO...do you think those are some signs that tell you something about them?I would say so.