The disciples come to Jesus asking HIM, "What is the sign of Thy coming and of the end of the world?"
Jesus tells them the first thing to look for.
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Matthew 24
And Jesus went out, and departed from the temple: and His disciples came to Him for to shew Him the buildings of the temple.2 And Jesus said unto them, See ye not all these things? verily I say unto you, There shall not be left here one stone upon another, that shall not be thrown down.
(All these great buildings that we admire will be destroyed at the end of this world, so Jesus warns HIS disciples not to take great pride in them for they will be destroyed.)
4 And Jesus answered and said unto them, Take heed that no man deceive you.
5 For many shall come in my name, saying, I am Christ; and shall deceive many.
They will come saying "Jesus is the Christ ... Jesus is Lord" ... and we will think they are Christians because they say that. And they will deceive many because they say that.
Those who are really Christians follow the Spirit of God:
Romans 8:14 For as many as are led by the Spirit of God, they are the sons of God.
When we see them display that wisdom that is from God, we know they are the sons of God and the real church.
It is not just a matter of talk.
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