'Unheard' in the Bible

So shall we come upon David in one of the places where he can be found, and we will fall on him as the dew falls [unseen and unheard] on the ground; and of him and of all the men who are with him, not even one will be left.

They took him and brought him to the Areopagus (Hill of Ares, the Greek god of war), saying, “May we know what this [strange] new teaching is which you are proclaiming?

It is actually reported that there is fornication among you, and of a kind unheard of even among the Gentiles--a man has his father's wife!