The parable of the mustard seed.
This parable stands related to the former. That pointed to the history of the growth of the seed; this points to the inherent vitality of the seed. That laid the emphasis on the field; this lays it on the seed. The simile is so exact that we are in danger of transferring a needful canon in the interpretation of parables, and to treat it as a realism. The parable illustrates the history of the kingdom of heaven in its outward manifestation, especially the smallness of its beginning contrasted with the greatness of its results.
I. THE KINGDOM OF GOD FINDS ITS APPROPRIATE SYMBOL IN A SEED WITH ITS INHERENT, VITAL, SELF-EXPANDING FORCE. This is true, whether we interpret the kingdom of God to refer to its essential principle—the dominion of the Divine Spirit over the human spirit; or to its outward manifestation in the visible Church of God—the gospel developing itself in the heart and life of mankind; or even to its instrument—the Divine Word. Gathering these together as all comprised in the idea of the kingdom of God, we must see it to be truly represented by a seeder living, inherently vital power. This parable leads us to think more particularly of the outward manifestation of the kingdom of God; and wherever we see it planted we sooner or later see signs of growth and extension. One of the first sentiments stirred in the breast of the newly converted is a desire for the conversion of others; and the first activities evoked from the new life are found in efforts to lead others to like blessing. Each believer becomes the germ of a Church; each is a self-propagating seed. From one may spring a thousand, nay, as many as the stars of heaven for multitude. So was it with the Church in the beginning—the little quickened seed in Jerusalem. So has it been in every age. To-day we joyfully witness the signs of this vitality on every hand.
II. A SECOND FEATURE OF THE KINGDOM OF GOD IS THE EXTREME SMALLNESS OF ITS ORIGIN. Still thought of as an outward manifestation, how small was its beginning! How little a seed! Judging Christ's work by the greatness of its aims, how small were his means! What books did he write? What organization did he frame? What cities did he build? What armies did he raise? What did he? Estimated by outward signs—a mere nothing. A few women and fewer men gathered; no multitude, no Church, no forms of worship, no writings. No; no; nothing. What then? Just a living seed dropped into the warm heart. Not more than a human heart could treasure—not more than Matthew could remember. The record of a brief life, with its few words; its few noble deeds of sincerity, love, and self-denial; and its sad death and marvellous resurrection. All the kingdom of God in that one life, all the heavenly treasure in that one earthen vessel; all in a "mustard seed,... less than all the seeds that are upon earth." But it grew to be "a tree."
III. This the third feature of the parable: THE ULTIMATE EXTENSION OF THE KINGDOM OF GOD. And the point of interest seems to be it grows beyond its probable limits, "greater than all the herbs;" yea, it "putteth out great branches, becometh a tree, so that the birds of the heaven" not only "lodge under the shadow" of it, but "in the branches thereof." Its growth is beyond, far beyond, what might have been reasonably expected. So we see to-day; so will it be more and more seen. These parables Jesus spake unto the multitude "as they were able to hear;" and privately then, as he now does to them who care to know, "he expounded all things."—G.