The Sacrifice requirement in the Old Testament, which is for the Atonement that Jesus made, requires the death, of the animal that was being sacrificed. However, the death alone could not make Atonement, which is only possible with the shedding of the blood of the animal, which is a type of what Jesus Christ did on the cross. No blood-shed, no Atonement, no Atonement, no salvation possible. This is Scripture
Leviticus 17:11, "For
the life of the flesh is in the blood, and I have given it to you upon the altar to make atonement for your souls;
for it is the blood that makes atonement for the soul"
Hebrews 9:12, "He entered once for all into the holy places, not by means of the blood of goats and calves
but by means of His own BLOOD, thus securing an eternal redemption"
verse 22, "Indeed, under the law almost everything is
purified with BLOOD, and
without the shedding of BLOOD there is no forgiveness of sins"