But when Christ appeared as a high priest of the good things to come, He entered through the greater and more perfect tabernacle, not made with hands, that is to say, not of this creation; and not through the blood of goats and calves, but through His own blood, He entered the holy place once for all, having obtained eternal redemption. For if the blood of goats and bulls and the ashes of a heifer sprinkling those who have been defiled sanctify for the cleansing of the flesh, how much more will the blood of Christ, who through the eternal Spirit offered Himself without blemish to God, cleanse your conscience from dead works to serve the living God? For this reason He is the mediator of a new covenant, so that, since a death has taken place for the redemption of the transgressions that were committed under the first covenant, those who have been called may receive the promise of the eternal inheritance.
The sacrifice of Jesus on the cross is sufficient for the forgiveness of sins. He entered once for all into the Holy Place to obtain eternal redemption for all mankind. Anyone who, through ignorance or misconduct intends to offer a sacrifice of atonement of sins does not recognize the value of the precious blood of Jesus shed on the cross.
Since the fall of man in Eden, God clearly established that the sin offering should be made from a blood sacrifice. In Genesis 3:21 we read: The Lord God made garments of skin for Adam and his wife, and clothed them. Adam and Eve had sinned and were cast out of paradise; but before leaving Eden they were dressed in animal skins. In a way, the blood of these animals was shed to cover the first sin of mankind. The sacrifice of Abel (Genesis 4: 4) was pleasing to God because it involved the sacrifice of his best sheep. Similarly, the instructions given by Moses beheld the sacrifice of lambs, sheep, calves, goats and other animals as atonement for the sins of Israel.
There are probably people who think the sacrifice of all these helpless animals is cruel. In a way, they had no fault to be treated that way, which is true. Who committed the sin? Obviously it was not the animals but we humans. But the Scriptures say very clearly that the wages of sin is death. Therefore, someone must pay with his or her life for the sins and shed all his or her blood. So God decided that the blood of innocent animals was spilled rather than the blood of human sinners.
However, animal blood not take away sin and, sometimes, sacrifice was not accepted by God. Only the blood of Jesus shed on the cross of Calvary was satisfactory and sufficient to cleanse sin to everyone who believes in Him as John the Baptist said, Jesus is the Lamb of God who takes away the sins of the world. Only His sacrifice is sufficient to save us, not what we do, but for what He has already done on the cross. God bless you.