Can someone explain Hebrews 9:22 (KJV) And almost all things are by the law purged with blood; and without shedding of blood is no remission.
Welcome Geophery. I will explain the meaning on the basis of what is in Scripture.
This goes back to the fact that the wages of sin (the penalty for sin) is death.
So either the sinner must die for his or sin, or God must provide a SINLESS SUBSTITUTE for the sinner. Because of the grace of God, God chose to provide sinless substitutes in the Old Testament, and all of them would prefigure the one sinless substitute for mankind -- the Lamb of God (the Lord Jesus Christ) who would take away the sins of the world. He would purge our sins.
So God instituted a system of animal sacrifices, using only clean animals (according to God). Their blood would be shed for the sins of the Israelites. Since the Bible says that the life of the flesh (the body) is in the blood (and this is corroborated through medical science) the shed blood of the animals was to pay the penalty for the sins of Israel. But their blood could not remove sins. It only covered sins for a season.
The crucifixion and the shedding of the blood of Christ were divine necessities. And that was accomplished at the cross. God already had a plan before He created the universe. The Lord Jesus Christ (who is fully God and fully sinless Man) would shed His own blood for the remission (forgiveness) of sins.
And without the shedding of blood there is no remission of sins. When a sinner believes on the Lord Jesus Christ, his or her past sins are fully forgiven and the blood of Christ is spiritually applied to that person's soul. Thus the soul is cleansed or washed in the blood of the Lamb. This is the only way that the sinner may be reconciled to God.
So the blood of Christ (as well as His sufferings and death) paid the full penalty for the sins of the whole world. The Bible says that God has purchased the Church with His own blood. That is a reference to Christ.