“For when Moses had spoken every precept to all the people according to the law, he took the blood of calves and of goats, with water, and scarlet wool, and hyssop, and sprinkled both the book, and all the people,”
King James Version (KJV)
9:19 He took the blood of calves - Or heifers. And of goats, with water, and scarlet wool, and hyssop - All these circumstances are not particularly mentioned in that chapter of Exodus, but are supposed to be already known from other passages of Moses. And the book itself - Which contained all he had said. And sprinkled all the people - Who were near him. The blood was mixed with water to prevent its growing too stiff for sprinkling; perhaps also to typify that blood and water, #John 19:34|. #Ex 24:7|,8
Heb 9:19 For when Moses had. For the events alluded to, see Ex 24:1-8. Spoken every precept to all the people according to the law. Ex 24:3. All that God had proclaimed in the ten commandments and the accompanying precepts (Ex 21:1-23:33) was written in the book of the covenant. This was read to the people, and they promised obedience (Ex 24:7). And sprinkled both the book, and all the people. Then the book and all the people were sprinkled with blood (Ex 24:8).