30 Let both grow together until the harvest. At harvest time I will tell the reapers, “First collect the darnel and tie it in bundles to be burned, but then gather the wheat into my barn.”’” 31 He gave them another parable: “The kingdom of heaven is like a mustard seed that a man took and sowed in his field. 32 It is the smallest of all the seeds, but when it has grown it is the greatest garden plant and becomes a tree, so that the wild birds come and nest in its branches.” 33 He told them another parable: “The kingdom of heaven is like yeast that a woman took and mixed with three measures of flour until all the dough had risen.”
Ketubot 111bBabylonian Talmud
It is stated: “With the kidney-fat of wheat” (Deuteronomy 32:14). The Sages said: In the future, each and every kernel of wheat will be as big as the two kidneys of the large ox. And do not be surprised that this is possible, as there was an incident involving a fox that nested inside a turnip, and they weighed this turnip, and they discovered that even discounting the space dug out by the fox, it still weighed sixty litra, as measured by the litra of Tzippori. Similarly, it is taught in a baraita that Rav Yosef said: There was an incident which occurred in the village of Shiḥin, in Eretz Yisrael, involving one whose father had left him three branches of mustard, one of which broke. And they discovered on this one branch alone nine kav of mustard. And with the wood of its large branches they roofed a booth for artisans. Similarly, Rabbi Shimon ben Taḥlifa said: Father left us a cabbage stalk and we would go up and down on it with a ladder, due to its great height.
Notes and References
"... This is the first parable in the discourse of Matthew 13 that does not receive an interpretation. None of the remaining parables, in fact, receives one. So the hearers (and readers) are left on their own to work out the implied interpretation. Furthermore, this is the last parable that Matthew draws from Mark, though the amount of agreement between the evangelists in their wording is small. Several verbal agreements between Matthew and Luke against Mark suggest the possibility of the influence of Q, which may have contained the parable as well — though those agreements may also be due to the influence of oral tradition on both Matthew and Luke. In the Parable of the Mustard Seed, the kingdom is likened to the situation of a man who planted a mustard seed in his field. In the ancient world the mustard seed was known for its smallness. From this "smallest" of seeds (it matters not that we know of smaller seeds) an amazingly large bush-like plant emerged, which at maturity was eight to ten feet in height (compare Babylonian Talmud, Ketuboth 111b, which refers to timber from a mustard tree sufficient in quantity to cover the roof of a potter's hut) and large enough to accommodate the nests of birds. This fact was so remarkable that it seems to have taken on a proverbial character ..."
Hagner, Donald A. The Challenge of Jesus’ Parables: Matthew's Parables of the Kingdom (pp. 113-114) William B. Eerdmans Publishing Company, 2000