When an individual makes the choice to give up something dear to them in order for others to survive, it sometimes happens that Deorus looks favorably upon that person and intervenes, making it so no sacrifice is necessary for their goals to come to pass. Deorus is a peculiar god due to the lack of worshippers. For if someone worships or prays to Deorus, hoping their sacrifice will meet with divine intervention, it's not truly a sacrifice. It's only those who fully believe they are giving fully of themselves whom Deorus smiles upon.
In keeping with that mindset, Deorus intervened between the battle of Lathander and Thrax in the Constellation War, when Thrax meant to destroy the incredibly powerful god by forgoing his own divinity. Deorus sacrificed his own instead.