The great New Testament scholar, Joachim Jeremias, said that the parables all pointed back to the speaker himself, Jesus. He is the treasure in a field, the priceless pearl. The unjust steward and the late laborers in the vineyard have said ‘Yes’ to Him. The tenants, the leaven, and the mustard seed are Jesus and His quiet radical effect around Him.
But they were interpreted by the early Church in the same direction. They saw correctly that the effect of Jesus and of the gospel in His post- resurrection Church were comparable. So the parable of the seed and sower has an interpretation which makes his connection clear.