Life of Alexander The Great
This long and painful pursuit of Darius – for in 11 days he marched 33 hundred furlongs – harassed his soldiers so that most of them were ready to give it up, chiefly for want of water.
While they were in distress, it happened that some Macedonians who had fetched water in skins upon their mules from a river they had found out came about noon to the place where Alexander was, and seeing him almost choked with thirst, presently filled a helmet and offered it to him …
Then he took the helmet in his hands, and looking round about, when he saw all those who were near him stretching their heads out and looking earnestly after the drink, he returned it again with thanks without tasting a drop of it.
“For,” said he, “if I alone should drink, the rest will be out of heart.”
The soldiers no sooner took notice of his temperance and magnanimity upon the occasion, but they one and all cried out to him to lead them forward boldly, and began whipping on their horses.
For whilst they had such a king they said they defied both weariness and thirst, and looked upon themselves to be little less than immortal.
The Life of Alexander The Great, Plutarch, c A.D. 46-120
(As cited in The 48 Laws of Power by Robert Greene, 1998, Penguin Books)