A kind of wild marjoram, used at the Passover (Ex. 12:22); for sprinkling purposes in the purification of lepers (Lev. 14:4, 51) and in the sacrifice of the red heifer (Num. 19:6; see also 1 Kgs. 4:33; Ps. 51:7). According to John (19:29), the sponge with the vinegar offered to our Lord on the cross was “put upon hyssop.” Matthew and Mark do not mention the hyssop but only the reed by which it was raised to Jesus’ mouth.