While the last chapter talked of the priest not being physically correct to perform the duty, as is the case with the mental and the log of sin. The priest must be purified to partake of the sacrifices brought forth by the people of Israel. If he was unclean, he was to not participate until he had been restored. The priest if he has a lingering issue, is still not to partake. Or if he has touched the dead or anything dead. Or if he spilt his seed from himself (masturbation). This isn't just tossed in there by accident. It is an instruction about masturbation and that it is not occur, or we are unclean.
The sacrifices of Israel were to feed not only the priests, but also their families. In this there were rules that God gives to Moses on their behalf. God has thought of every transgression possible, if we only know where to look. Often our mind is closed off from God and His Word. Allow God to enter into your soul and guide you as He guided the prophets. Accept Him into your life and let Him go to work for you.
The sacrifices to God were to remain pure and perfect as was possible. As Christ was perfect, these sacrifices were to be like Him. We shall remember the perfection of Christ and give thanks for His sacrifice for us. The Cross and Christ are aged. Yet, they live forever. Be influenced by forever. Accept forever in totality.