Another parable spoke he unto them;
The kingdom of heaven is like unto leaven, which a woman took, and hid in three measures of meal, till the whole was leavened.
All Commentaries on Matthew 13:33 Go To Matthew 13
Rabanus Maurus
AD 856
He says, “Until the whole was leavened,” because that love implanted in our mind ought to grow until it changes the whole soul into its own perfection; which is begun here, but is completed hereafter.