1. Animal sacrifice could not make them perfect (1-4)

If the sacrifices prescribed for sins in the Old Testament had power to make people holy, the author says, those who offered them would have stopped feeling guilty and they would not have needed to offer them anymore. But as we know in our hearts, the power of guilt is not so easy to get rid of. In fact, it is obvious that the blood of animals cannot make atonement for human beings' spiritual sin.

2. Made holy once for all (5-18)

Jesus fulfilled the scriptures that prophesied a new covenant which would put an end to sacrifices and burnt offerings. We don't need to make sacrifices for our sin, because Jesus' sacrifice has made us perfect once and for all. Now, by the power of his grace, we are being made holy day by day.