“It is lawful (46) to kill with impunity one who attacks by night in the fields, or blockades the highways, and lies in ambush for passersby, even if he be a soldier. For indeed it is doubly better to attack, than for an injury suffered to be healed, and to seek vengeance.
“Note 46. He is not a murderer who, in peril of his life, kills an attacker, nor ought anyone to wait for the first blow, because it might be irreparable.”