This scripture is important because it lays the foundation of what Jesus came to do. He came to be our High Priest to establish a different covenant between God and mankind (verse 6) because He made the old one obsolete (verse 13). Now read Hebrews 9:11-22:
11 But Christ came as High Priest of the good things to come, with the greater and more perfect tabernacle not made with hands, that is, not of this creation.
12 Not with the blood of goats and calves, but with His own blood He entered the Most Holy Place once for all, having obtained eternal redemption.
13 For if the blood of bulls and goats and the ashes of a heifer, sprinkling the unclean, sanctifies for the purifying of the flesh,
14 how much more shall the blood of Christ, who through the eternal Spirit offered Himself without spot to God, cleanse your conscience from dead works to serve the living God?
15 And for this reason He is the Mediator of the new covenant, by means of death, for the redemption of the transgressions under the first covenant, that those who are called may receive the promise of the eternal inheritance.
16 For where there is a testament, there must also of necessity be the death of the testator.
17 For a testament is in force after men are dead, since it has no power at all while the testator lives.
18 Therefore not even the first covenant was dedicated without blood.
19 For when Moses had spoken every precept to all the people according to the law, he took the blood of calves and goats, with water, scarlet wool, and hyssop, and sprinkled both the book itself and all the people,
20 saying, “This is the blood of the covenant which God has commanded you.”
21 Then likewise he sprinkled with blood both the tabernacle and all the vessels of the ministry.
22 And according to the law almost all things are purified with blood, and without shedding of blood there is no remission. (NKJV)