Matthew 10:16
Behold, I am sending you out as sheep in the midst of wolves, so be wise as serpents and innocent as doves.

Proverbs 30:18-19
Three things have been too wonderful for me, Yea, four that I have not known: The way of the eagle in the heavens, The way of a serpent on a rock, The way of a ship in the heart of the sea, And the way of a man in youth.