Verse 5 “Your lamb shall be without blemish, a male of the first year: ye shall take it out from the sheep, or from the goats:”
Jesus, the Lamb of God, is without blemish and with out spot. He had no stain of sin upon Him (See I Peter 2:22; Hebrews 4:15; II Corinthians 5:21). Only a sinless Jesus could take away the sins of a sinner like me (John 1:29).