Friends! Fighting Danaans! Aides-in-arms of Ares!
Fight like men, my comrades – call up your battle-fury!
You think we have reserves in the rear to back us up?
Some stronger wall to shield our men from disaster?
No, there’s no great citadel standing near with towers
where we could defend ourselves and troops could turn the tide.
No – we’re here on the plain of Troy – all Troy’s in arms!
Dug in, backs to the sea, land of our fathers far away!
Fight – the light of safety lies in our fighting hands,
not spines gone soft in battle!

– Homer

The Iliad, Book 15, lines 851-860. This is Great Ajax’s battle cry to his comrades to motivate them to hold off the Trojan attack on the Greek ships. He tells them bluntly that it’s do or die, there are no reserves to back them up, and the light of safety (metaphor) lies in their own fighting hands. A terrifying moment for the men!