The idea of a blood sacrifice to win over the souls of mankind and become a substituted atonement was just the beginning of the ignorance that would develop the Dark Ages.
This is misperception on your part, Amillus.
The reason for ordination of the sacrifices were two part. One has to do with the vey serious issue of Conscience in humanity, which God cares about. And, long beofe the disicplines of Psychology and Psychiatry came to be.
, a sign to humanity what, "The Lamb of God", would accomplish for humanity, with respect to peace with God, also.
Put yourself in the position of the burdened petitioner who made sacrifice, in the Old Testament, according to God's commandments.
Who, after leaving the sacrifice with the priest, knew they had peace with the Almighty.
However, this situation and system was abused, also, which God addressed in the Word. Telling them that their sacrifices were in vain if their heart was not sincere, and if they treated their fellow humanity wrongly.