'Proof' in the Bible

"By what proof," asked Zechariah, "shall I know this? For I am an old man, and my wife is far advanced in years."

The reply of Jesus was, "It is said, 'Thou shalt not put the Lord they God to the proof.'"

Then Jesus ordered him, "Don't tell anyone. Instead, go and show yourself to the priest and make an offering for your cleansing, just as Moses commanded, as proof to the authorities."

hypocrites! the face of the earth and of the heaven ye have known to make proof of, but this time -- how do ye not make proof of it?