It's amazing to read the details of the old laws in Leviticus. Life back then centered around making animal sacrifices, food offerings and other strict rituals to cleanse oneself of sin, guilt and disease in order to be acceptable to the Lord (holy and to be honored always). And to think, all these rules carried a much lighter load compared to the alternative of human sacrifice and slavery.
And these days, thank God for Christ whose blood through death cleanses away all sin - we are spoiled! As Jesus said "...for my yoke is easy and my burden is light." (Matthew 11:30). No animals to slaughter, just believe Jesus is the son of God, ask for forgiveness and it is given along with eternal life. Amen.
p.s. if you have trouble believing, ask God to help you with it. Ask God to open your heart and mind to the presence of Jesus.