E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Every bullet has its billet. Nothing happens by chance, and no act
is altogether without some effect. There is a divinity that shapes our ends, rough hew them as we will. Another meaning is this: an arrow or bullet is not discharged at random, but at some mark or for some deliberate purpose.
Let the arrow fly that has a mark.Cæsar Borgia, chap. xx.