The Art of War by active 6th century B.C. Sunzi

7. The general who is skilled in defence hides in the most secret

recesses of the earth; [Literally, "hides under the ninth earth," which is a metaphor indicating the utmost secrecy and concealment, so that the enemy may not know his whereabouts."] he who is skilled in attack flashes forth from the topmost heights of heaven. [Another metaphor, implying that he falls on his adversary like a thunderbolt, against which there is no time to prepare. This is the opinion of most of the commentators.] Thus on the one hand we have ability to protect ourselves; on the other, a victory that is complete.