Mustard. Several kinds of mustard-plant grow in the Holy Land, either wild, as the charlock, Sinapis arvensis, and the white mustard, S. Alba, or cultivated, as S. nigra, which last seems the one intended in the Gospel. Our Lord compares the kingdom of God to a mustard seed (Matt., xiii, 31-2), a familiar term to mean the tiniest thing possible (cf. Talmud Jerus. Peah, 7; T. Babyl. Kethub., iiib), "which a man … sowed in his field" and which "when it is grown up, it is greater than all herbs"; the mustard tree attains in Palestine a height of ten feet and is a favourite resort of linnets and finches.
The black mustard grew wild in Palestine on the shores of Galilee. This herb reached 1.8 to 2.4 m. (60 to 8 ft.) in height and as covered with yellow flowers. The seeds were used to flavor meat and vegetables, and were a favorite food of the birds.