Over and again in the early chapters of Leviticus as the prescriptions for offerings are laid out, we’re reminded that a sacrifice to God must be perfect. A burnt offering from the herd or flock must be “without defect” (1:3, 10); the sin offering for a priest must be “a young bull without defect” (4:3), for a leader “a male goat without defect” (v.23), for an ordinary person “a female goat without defect” (v.28) or a female lamb “without defect” (v.32), and so also for the guilt offerings (chs. 5-6).
Certainly God deserves the best, and whatever is to be given to God must be from the best. But I think also there is a symbolism at work here, the sacrifice of purity to cleanse away impurity. A beast already blemished would be a poor offering to cleanse the blemish from a human heart; and since these offerings are ineffective in themselves but only point forward to Christ, the ultimate message is how He was qualified as the sin bearer because He was “without defect” morally.
“The blood of goats and the ashes of a heifer sprinkled on those who are ceremonially unclean sanctify them so that they are outwardly clean. How much more, then, will the blood of Christ, who through the eternal Spirit offered himself unblemished to God, cleanse our consciences from acts that lead to death, so that we may serve the living God!” (Heb. 9:13-14)
It’s remarkable to think on the life of Christ, that He committed no sin, and that while it would be reductionistic to make this the whole of it, to some extent we may say that He resisted temptation all His life for us. Only in so doing could He bear our sins on the cross. Only a pure sacrifice can wash away the stain of sin.
Christians, called to holiness, are only asked to live out proper gratitude for what the Holy One has done for us. The world thinks righteous living a terrible burden; we must think rightly, and see righteous living as a joyous response, to Jesus Christ our Lord.