Exodus 12:22

12:22 Take a branch of hyssop, dip it in the blood that is in the basin, and apply to the top of the doorframe and the two side posts some of the blood that is in the basin. Not one of you is to go out the door of his house until morning.

Numbers 19:18

19:18 Then a ceremonially clean person must take hyssop, dip it in the water, and sprinkle it on the tent, on all its furnishings, and on the people who were there, or on the one who touched a bone, or one killed, or one who died, or a grave.

Psalms 51:7

51:7 Sprinkle me with water and I will be pure;

wash me and I will be whiter than snow.