'Sign' in the Bible

Then the Jews put this question to him: What sign of authority have you to give us, seeing that you do these things?

Now this is the second sign which Jesus did after he had come out of Judaea into Galilee.

And when the people saw the sign which he had done, they said, Truly, this is the prophet who is to come into the world.

So they said, What sign do you give us, so that we may see and have faith in you? What do you do?

And a great number of people came to him, saying, John did no sign: but everything John said of this man was true.

And that was the reason the people went out to him, because it had come to their ears that he had done this sign.

Making a sign to him, Simon Peter said, Who is it he is talking about?