The parable of the mustard tree is repeated twice in the Christian Bible gospels, and variants of the story are part of the Buddhist religion and in Indian culture as well. While black mustard, or Brassica Nigra, is not technically a tree, it grows large enough to be tree-like with tiny seeds that are popular with birds.
Brassica Nigra, or black mustard, is an erect plant that grows to 8 feet tall and can resemble a tree. Although not technically a tree, it is sometimes called the mustard tree, and is widely considered to be the plant referenced as such in the biblical parable of the same name. Brassica Nigra grows on grassy plains.
The parable of the mustard tree is found in the biblical books of Luke and Matthew. It centers around the idea that the tiny mustard seed grows into a large tree-like plant, which is also a characteristic of the kingdom of heaven. This story is considered a parable for the way life starts from tiny beginnings as well.
There is some controversy over whether Brassica Nigra is indeed the plant referenced in the biblical parable of the mustard tree. The most obvious controversy stems from the fact that black mustard is not actually a tree at all. It is a very large plant. The Bible indicates that birds nest in the mustard tree, which does not happen in black mustard. Some birds, however, do land on the plant to eat the seeds. Despite the controversy, black mustard is still widely considered the mustard tree of the Bible.
Mustard is a pungent plant that has many culinary and medicinal uses. Folk medicine calls for a mustard plaster to be applied externally for ailments such as arthritis. Mustard oil is high quality, and useful in medications because it does not go rancid. Surgeons use mustard seed flour to make their hands aseptic. The seed of Brassica Nigra is the basis of common table mustard, used in many types of cuisine and as a condiment.