Hebrews 9:19-22
For after Moses had declared every commandment of the law to all the people, he took the blood of calves and goats and [mixed it] with water, then sprinkled both the scroll [of the Agreement] and all the people with a hyssop branch covered by red wool [dipped in the mixture].
Hebrews 11:28
By [having] faith, he established the Passover Festival [Note: This festival was first celebrated in Egypt by the fleeing Israelites, then observed annually in commemoration of that event], and had [lambs'] blood sprinkled [on the door jambs] to prevent the one who destroyed the firstborn children from touching them. [See Ex. 12:23].
Hebrews 12:24
and to Jesus, the Mediator of a New Agreement [between God and mankind], and to the sprinkled blood [of Jesus], which says better things [to us] than [the blood of] Abel did. [Note: The contrast seems to be that "Abel's blood called for vengeance and death (See Gen. 4:10) whereas the blood of Christ provides mercy and life"].
1 Peter 1:2
These people have been [specially] selected, and [their acceptance was] pre-planned by God the Father, and they were set apart through [the work of] the Holy Spirit. This resulted in their obedience and sprinkling [Note: This is a figurative reference to the Old Testament practice of cleansing, See Exodus 24:7-8] by the blood of Jesus Christ. May God's unearned favor and peace be continually upon you.