Thus said the Lord to me, "Go and buy yourself a linen loincloth, and put it on your loins, but do not dip it in water." So I bought a loincloth according to the word of the Lord, and put it on my loins. And the word of the Lord came to me a second time, saying, "Take the loincloth that you bought and are wearing, and go now to the Euphrates, and hide it there in a cleft of the rock." So I went, and hid it by the Euphrates, as the Lord commanded me.
And after many days the Lord said to me, "Go now to the Euphrates, and take from there the loincloth that I commanded you to hide there." Then I went to the Euphrates, and dug, and I took the loincloth from the place where I had hidden it. But now the loincloth was ruined; it was good for nothing.
Then the word of the Lord came to me: Thus says the Lord: Just so I will ruin the pride of Judah and the great pride of Jerusalem. This evil people, who refuse to hear my words, who stubbornly follow their own will and have gone after other gods to serve them and worship them, shall be like this loincloth, which is good for nothing. For as the loincloth clings to one's loins, so I made the whole house of Israel and the whole house of Judah cling to me, says the Lord, in order that they might be for me a people, a name, a praise, and a glory. But they would not listen.
He put before them another parable: "The kingdom of heaven is like a mustard seed that someone took and sowed in his field; it is the smallest of all the seeds, but when it has grown it is the greatest of shrubs and becomes a tree, so that the birds of the air come and make nests in its branches."
He told them another parable: "The kingdom of heaven is like yeast that a woman took and mixed in with three measures of flour until all of it was leavened."
Jesus told the crowds all these things in parables; without a parable he told them nothing. This was to fulfill what had been spoken through the prophet: "I will open my mouth to speak in parables; I will proclaim what has been hidden from the foundation of the world."
Jesus mentions matters "hidden since the foundation of the world," quoting the opening lines of Psalm 78, "Listen, my people, to my teaching. I will open my mouth in a parable, I will utter mysteries from of old." This long psalm of seventy-two verses recounts the history of Israel, from the exodus from Egypt to the choice of David as king and Mount Zion as the sacred site of the temple. Through Ps 78, the first reading about Moses and the golden calf becomes a part of God's eternal mystery of mercy and salvation, hidden since the creation of the world.
We all have a share in Israel's promise and Israel's blame. Like Israel we share the privilege and pledge of being the chosen people, intimately united with God. In Jeremiah we find the image of the loincloth to manifest this intimacy. "As the loincloth clings to the loins, so had I made the whole house of Israel cling to me," says the Lord.
The two parables in today's gospel are an image of Jesus' own ministry. His work in Galilee is like the mustard seed and the leaven; it is very small scale and to outsiders would have looked somewhat unpromising. Jesus has not been sweeping all before him. He has been going about his work quietly without fanfare. Yet, the parables suggests that these small beginnings are the promise of something wonderful to come, just as the mustard seed becomes a tree where the birds of the air build their nests and the tiny leaven has a huge impact on three measures of flower. Humble beginnings can have an extraordinary outcome when the work in question is God's work. There is an encouragement to us all to keep doing the little bit of good we are able to do. It may not seem much in our own eyes or in the eyes of others, yet God can work powerfully through whatever little good we do, in ways that will surprise us. We can all plant the equivalent of the mustard seed; we can all be the equivalent of the leaven. The little initiative, the small gesture, the offer of help, can all bear fruit in ways that we could never have imagined at the time. The Lord can work powerfully through our smallest efforts if they are done out of love for him. Our calling is often to plant some good seed and to trust that the Lord will do the rest.