Though the Gospel of Thomas separates the parable of the mustard seed1 and the parable of the leaven2 and Mark does not have the parable of the leaven entirely3, the pairing of the parables in Luke and Matthew bring the similarities of both to light. The parables are connected in that both are about the small acts of women and men who, when paired with the mysterious acts of God, bring forth the Kingdom of God in the present world.
The first connection between the parables is that both parables start with a person in the parable taking action. The man planted the mustard seed in the ground and the woman hid the leaven in the flour. Neither person sits back and waits for something to happen. They take initiative. The humans in the parables act upon the thing that will, for a time, be hidden to those looking on the outside. The Kingdom of God is not something one sits back and waits for. Jesus' ministry makes it clear we are to be active participants in the bringing forth of the kingdom.
The second connection between the mustard seed and the leaven is that both enact change by an unseen force. In Mark Jesus notes another farmer who doesn’t know how it is that seeds grow into larger plants.4 The man who plants the mustard seed, I’m sure, has no additional insights into how mustard seeds become trees. The woman of Jesus' parable who uses a small amount of leaven to leaven a larger amount of dough also wouldn’t have a clear understanding of how the leavening process worked. The seed and the leaven grow and expand by the unseen power of God. Men and women in these parables must exercise faith in the unseen Divine Power with the expectation that God will cause something to happen to that which is hidden from sight.
Finally, both parables point to the Kingdom of God being alive and well in the present. In both parables something small and hidden from view by the faithful actions of humans grows into a central element of a present community through the invisible power of God. Jesus has many sayings about the eschatological future, but in these two parables the focus is on the present. The community of birds build their homes together in the branches of the tree. The Galilean woman comes together with the women of her village to bake bread that is the be shared with the entire community.5 In these parables Jesus is teaching that if we take his small teachings of love of God and neighbor and place them – without great show or spectacle – within our communities that God can make great things happen and we can experience the joys of the Kingdom of God in the present age.
Matt 13:31-32, Mark 4:30-32, Luke 13:18-19
Matt 13:33, Luke 13:20-21
Klyne Snodgrass, Stories with Intent: A Comprehensive Guide to the Parables of Jesus (Grand Rapids, Mich: William B. Eerdmans Pub. Co, 2008)., pg. 218
Amy-Jill Levine, Short Stories by Jesus: The Enigmatic Parables of a Controversial Rabbi (New York, NY: HarperOne, 2014)., pg. 125