It is the smallest of all seeds is translated “There is no smaller seed” by Die Bibel im heutigen Deutsch. Although the mustard seed is not actually the smallest of all seeds, some commentators note that the mustard seed was used in a proverb common among Jewish teachers to denote the smallest thing or the smallest amount possible. In Jesus’ time mustard was cultivated both for its seed and as a vegetable. Translators need to be sure it is clear that the text is referring to mustard seeds in general, not to the specific seed the man sows in the parable. Hence some translations will say “the seed of a mustard plant is the smallest of any kind of seed.”

But when it has grown draws the contrast between the small seed and the large plant which it produces upon maturity. No concern is given to the process or growth. In languages where it is not seeds that grow, it may be necessary to say “But when the plant has grown.”

Shrubs (Good News Translation “plants,” New English Bible “garden-plant”) refers to edible garden plants, that is, vegetables. If a language has a general word for “plants” that can be used for shrubs, that is best. However, “bushes” or “plants people grow (for food)” are other possibilities. Each language divides the various sizes and types of plants into categories differently, rarely corresponding to English categories of “bush,” “shrub,” and “tree.” Translators will have to use whatever term from their language seems to be most appropriate.

When fully grown, the mustard plant becomes a tree of eight to twelve feet in height. Birds of the air (better “birds”; see comment at 6.26) are attracted to the mustard tree because of it shade and its fruit, though they do not normally nest in it. Commentators note that the reference to a huge tree in which birds come to roost is used symbolically in the Scriptures of a powerful kingdom which protects its dependent states (see Ezek 17.23; 31.6; Dan 4.20-22). In apocalyptic literature and in the writings of Jewish teachers, birds sometimes represent Gentiles who come to seek refuge with Israel.

There are languages that have no word for tree in general, naming instead each particular species. In that case translators should pick some local tree that is about the same height and say “grows to be like __________,” using the name of the local tree.

Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on the Gospel of Matthew. (UBS Handbook Series). New York: UBS, 1988. For this and other handbooks for translators see here .