Does God really require the sacrifice of blood for the atonement of sins?
Yes, God requires the shedding of blood as a sacrifice for the atonement of sin (Hebrews 9:22), along with burnt offerings of perfect animals as consecration of what is holy and for other gifts that are pleasing to him. Not to go in-depth into the theology of the shedding of blood, the main reason was that through sin came death and those who sinned died in their sins. But the innocent blood of the blameless could be substituted for the sins of the guilty, though not the blood of an innocent man since this was a sin in itself, so a clean animal (those acceptable for eating) without blemish was required.
