It seems that hyssop was some sort of cereal plant that grew in Palestine. When several stalks were tied together it made a good brush, and as such was used to apply blood in some of the Jewish rituals (Exodus 12:22; Leviticus 14:4; Leviticus 14:6; Leviticus 14:49-52; Numbers 19:2-6; Psalms 51:7; Hebrews 9:19). Its strong stalk enabled it to be used to pass a sponge of vinegar up to Jesus as he hung on the cross (John 19:29).