Numbers 24:21
And he looked on the Kenites, and took up his parable, and said, Strong is thy dwellingplace, and thou puttest thy nest in a rock. And he looked on the Kenites, and took up his parable, and said, Strong is thy dwellingplace, and thou puttest thy nest in a rock.
The utterance belongs to Balaam's prophecy directed against the enemies surrounding Israel. Within that prophecy the Kenites are portrayed as secure, occupying a strong dwellingplace with their nest fixed high in the rock. Yet the prophecy does not end with their security, but closes by foretelling their utter and complete destruction.