Note that the Scriptures repeatedly refer to the use of Hyssop for medicinal and cleansing purposes.Psalm 51:7
Purify me with hyssop, and I shall be clean; wash me, and I shall be whiter than snow.
Numbers 19 – The Ashes of the Red Heifer Sacrifice
 And the LORD spoke unto Moses and unto Aaron, saying,
 This is the ordinance of the law which the LORD hath commanded, saying, Speak unto the children of Israel, that they bring thee a red heifer without spot, wherein is no blemish, and upon which never came yoke:
 And ye shall give her unto Eleazar the priest, that he may bring her forth without the camp, and one shall slay her before his face:
 And Eleazar the priest shall take of her blood with his finger, and sprinkle of her blood directly before the tabernacle of the congregation seven times:
 And one shall burn the heifer in his sight; her skin, and her flesh, and her blood, with her dung, shall he burn:
 And the priest shall take cedar wood, and hyssop, and scarlet, and cast it into the midst of the burning of the heifer.
 Then the priest shall wash his clothes, and he shall bathe his flesh in water, and afterward he shall come into the camp, and the priest shall be unclean until the even.
 And he that burneth her shall wash his clothes in water, and bathe his flesh in water, and shall be unclean until the even.
 And a man that is clean shall gather up the ashes of the heifer, and lay them up without the camp in a clean place, and it shall be kept for the congregation of the children of Israel for a water of separation: it is a purification for sin.
 And he that gathereth the ashes of the heifer shall wash his clothes, and be unclean until the even: and it shall be unto the children of Israel, and unto the stranger that sojourneth among them, for a statute for ever.
 This is the law, when a man dieth in a tent: all that come into the tent, and all that is in the tent, shall be unclean seven days.
 And every open vessel, which hath no covering bound upon it, is unclean.
 And whosoever toucheth one that is slain with a sword in the open fields, or a dead body, or a bone of a man, or a grave, shall be unclean seven days.
 And for an unclean person they shall take of the ashes of the burnt heifer of purification for sin, and running water shall be put thereto in a vessel:
 And a clean person shall take hyssop, and dip it in the water, and sprinkle it upon the tent, and upon all the vessels, and upon the persons that were there, and upon him that touched a bone, or one slain, or one dead, or a grave:
 And the clean person shall sprinkle upon the unclean on the third day, and on the seventh day: and on the seventh day he shall purify himself, and wash his clothes, and bathe himself in water, and shall be clean at even.
 But the man that shall be unclean, and shall not purify himself, that soul shall be cut off from among the congregation, because he hath defiled the sanctuary of the LORD: the water of separation hath not been sprinkled upon him; he is unclean.
 And it shall be a perpetual statute unto them, that he that sprinkleth the water of separation shall wash his clothes; and he that toucheth the water of separation shall be unclean until even.
 And whatsoever the unclean person toucheth shall be unclean; and the soul that toucheth it shall be unclean until even.
Leviticus 14 – Treating Skin Disease
 And the LORD spake unto Moses, saying,
 This shall be the law of the leper in the day of his cleansing: He shall be brought unto the priest:
 And the priest shall go forth out of the camp; and the priest shall look, and, behold, if the plague of leprosy be healed in the leper;
 Then shall the priest command to take for him that is to be cleansed two birds alive and clean, and cedar wood, and scarlet, and hyssop:
 And the priest shall command that one of the birds be killed in an earthen vessel over running water:
 As for the living bird, he shall take it, and the cedar wood, and the scarlet, and the hyssop, and shall dip them and the living bird in the blood of the bird that was killed over the running water:
 And he shall sprinkle upon him that is to be cleansed from the leprosy seven times, and shall pronounce him clean, and shall let the living bird loose into the open field.
Intriguingly, while Jesus Christ was dying on the Cross the soldiers offered Him a long reed to which was tied a sponge with vinegar (which would refresh His thirst) and hyssop (which would refresh Him to some extent by its aromatic scent. “Now there was set a vessel full of vinegar: and they filled a spunge with vinegar, and put it upon hyssop, and put it to his mouth.”
During the Exodus the Jewish slaves were commanded to use Hyssop to sprinkle the blood of the Paschal lamb on the doorposts of the Jewish dwellings in Egypt on the night of Passover. This was an act of obedience and faith to mark their families so the Angel of Death would “pass over” their home and family and not kill their firstborn sons.
“And ye shall take a bunch of hyssop, and dip it in the blood that is in the bason, and strike the lintel and the two side posts with the blood that is in the bason; and none of you shall go out at the door of his house until the morning.”
In the New Testament the writer of the book of Hebrews also mentions Hyssop: “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,”