Bede the Venerable
Catena Aurea · Lukasevangelium 13
Then said he, Unto what is the kingdom of God like? and whereunto shall I resemble it? It is like a grain of mustard seed, which a man took, and cast into his garden; and it grew, and waxed a great tree; and the fowls of the air lodged in the branches of it. And again he said, Whereunto shall I liken the kingdom of God? It is like leaven, which a woman took and hid in three measures of meal, till the whole was leavened. He next likens the kingdom of God to leaven, for it follows, And again he says, Whereunto shall I liken it? It is like to leaven, &c.
Or, by the leaven He speaks of love, which kindles and stirs up the heart; the woman, that is, the Church, hides the leaven of love in three measures, because she bids us love God with all our hearts, all our minds, and all our strength. And this until the whole is leavened, that is, until love moves the whole soul into the perfection of itself, which begins here, but will be completed hereafter.