Here is, I. The gospel's progress foretold in two parables, which we had before, Mat 13:31-33. The kingdom of the Messiah is the kingdom of God, for it advances his glory; this kingdom was yet a mystery, and people were generally in the dark, and under mistakes, about it. Now, when we would describe a thing to those that are strangers to it, we choose to do it by similitudes. "Such a person you know not, but I will tell you whom he is like;" so Christ undertakes here to show what the kingdom of God is like (Luk 13:18): "Whereunto shall I liken the kingdom of God? Luk 13:20. It will be quite another thing from what you expect, and will operate, and gain its point, in quite another manner." 1. "You expect it will appear great, and will arrive at its perfection all of a sudden; but you are mistaken, it is like a grain of mustard-seed, a little thing, takes up but little room, makes but a little figure, and promises but little; yet, when sown in soil proper to receive it, it waxes a great tree," Luk 13:19. Many perhaps were prejudiced against the gospel, and loth to come in to the obedience of it, because its beginning was so small; they were ready to say of Christ, Can this man save us? And of his gospel, Is this likely ever to come to any thing? Now Christ would remove this prejudice, by assuring them that though its beginning was small its latter end should greatly increase; so that many should come, should come upon the wing, should fly like a cloud, to lodge in the branches of it with more safety and satisfaction than in the branches of Nebuchadnezzar's tree, Dan 4:21. 2. "You expect it will make its way by external means, by subduing nations and vanquishing armies, though it shall work like leaven, silently and insensibly, and without any force or violence, Luk 13:21. A little leaven leaveneth the whole lump; so the doctrine of Christ will strangely diffuse its relish into the world of mankind: in this it triumphs, that the savour of the knowledge of it is unaccountably made manifest in every place, beyond what one could have expected, Co2 2:14. But you must give it time, wait for the issue of the preaching of the gospel to the world, and you will find it does wonders, and alters the property of the souls of men. By degrees the whole will be leavened, even as many as are, like the meal to the leaven, prepared to receive the savour of it."
II. Christ's progress towards Jerusalem recorded: He went through the cities and villages, teaching and journeying, Luk 13:22. Here we find Christ an itinerant, but an itinerant preacher, journeying towards Jerusalem, to the feast of dedication, which was in the winter, when travelling was uncomfortable, yet he would be about his Father's business; and therefore, whatever cities or villages he could make in his way, he gave them a sermon or two, not only in the cities, but in the country villages. Wherever Providence brings us, we should endeavour to be doing all the good we can.

The kingdom - is like a grain of mustard seed - See on Mat 13:31 (note).

And again he said,.... That is, Jesus, as the Syriac and Persic versions express it; besides the parable of the grain of mustard seed, that also of the leaven hid in three measures of meal:

whereunto shall I liken the kingdom of God; either the Gospel of the kingdom, and the mysteries of it; or the church, which is Christ's kingdom; or the grace of God in the heart, which makes meet for the kingdom of glory; the first seems rather to be intended; See Gill on Mat 13:33.

MISCELLANEOUS TEACHINGS. (Luk 13:18-30)

mustard seed . . . leaven--(See on Mar 4:30-32). The parable of "the Leaven" sets forth, perhaps, rather the inward growth of the kingdom, while "the Mustard Seed" seems to point chiefly to the outward. It being a woman's work to knead, it seems a refinement to say that "the woman" here represents the Church, as the instrument of depositing the leaven. Nor does it yield much satisfaction to understand the "three measures of meal" of that threefold division of our nature into "spirit, soul, and body," (alluded to in Th1 5:23) or of the threefold partition of the world among the three sons of Noah (Gen 10:32), as some do. It yields more real satisfaction to see in this brief parable just the all-penetrating and assimilating quality of the Gospel, by virtue of which it will yet mould all institutions and tribes of men, and exhibit over the whole earth one "Kingdom of our Lord and of His Christ." (See on Rev 11:15).