The person who put the initial aggressive killer to death was given a special name : go ` el haddam , the blood-avenger or blood-redeemer ( Num . 35 : 19 , etc. ) . The executor of the law of blood-revenge who personally put the initial aggressive killer to death was given a special designation : go ` el haddam , the blood-avenger or blood-redeemer ( Book of Numbers 35 : 19 , etc. ) .