All who make carved images are vanity, and the things they delight in are worthless. Their own witnesses neither see, nor know; that they may be put to shame. Who fashioned a god, or cast an idol that is useless? No one considers in his heart; neither is there knowledge nor understanding to say: 'I have burned the half of it in the fire.'
vayikra “He called to Moses” Leviticus 1 – 5:26
The process of sacrificing in the “mishkan” – the Tabernacle - was a complex system transferring human action symbolically to the consecrated animals. The “kohainim” - the priests - would sprinkle some of the blood onto the “mitzbayach” – the altar - as part of the ceremony symbolizing that it should have been the sinner’s blood not the animals'. It is the animal and its blood that becomes a substitution for the sins of the human. Sinful actions and sinful thoughts including sexual inappropriateness like intercourse with a woman who is menstruating indicated at the lower right can be mitigated by sacrifice.