18 That is why even the first covenant was put into effect with the blood of an animal. 19 For after Moses had read each of God's commandments to all the people, he took the blood of calves and goats, along with water, and sprinkled both the book of God's law and all the people, using hyssop branches and scarlet wool. 20 Then he said, "This blood confirms the covenant God has made with you."
Matthew Henry's Commentary on Hebrews 9:18-20
Commentary on Hebrews 9:15-22
(Read Hebrews 9:15-22)
The solemn transactions between God and man, are sometimes called a covenant, here a testament, which is a willing deed of a person, bestowing legacies on such persons as are described, and it only takes effect upon his death. Thus Christ died, not only to obtain the blessings of salvation for us, but to give power to the disposal of them. All, by sin, were become guilty before God, had forfeited every thing that is good; but God, willing to show the greatness of his mercy, proclaimed a covenant of grace. Nothing could be clean to a sinner, not even his religious duties; except as his guilt was done away by the death of a sacrifice, of value sufficient for that end, and unless he continually depended upon it. May we ascribe all real good works to the same all-procuring cause, and offer our spiritual sacrifices as sprinkled with Christ's blood, and so purified from their defilement.