כי ביום הזה יכפר עליכם . I have written a great deal about this as a separate treatise.

אשר יעשה אותם האדם וחי בהם . This verse suggests that a person should do everything he does with determination and dispatch as this is the meaning of וחי. Rashi has already explained this in connection with the ten requirements to make the cup of benediction when saying grace effective (Berachot 50a). One of these ten factors is that it be חי, fresh, potent. This paragraph is followed by the laws dealing with incestuous relationships, i.e the exhortation that we must sanctify ourselves in our sexual lives and demonstrate that we can conquer our carnal urges. I have already explained that the test of sanctification lies in one's preparedness to forego gratifications of the body that are permissible.