Mustard seed
In Matthew 13:31, the mustard seed represents the good we have before developing a spiritual orientation; it is the smallest of all the seeds, because we often think that we do good on our own. Anything we do on our own is evil through and through, but since we are engaged in the process of being reborn, we have a trace — the smallest possible trace — of goodness. (Arcana Coelestia 55[3, 4])
Matthew 13:31
31
He set another parable before them, saying, "The Kingdom of Heaven is like a grain of mustard seed, which a man took, and sowed in his field;