Mark now gives additional seed parables (see 4:3–20). They all focus on "the mystery of the kingdom of God" (4:11). The parables of the seed growing secretly (4:26–29) and the mustard seed (4:30–32) show different stages of seed growth.
The kingdom of God is hidden (4:21). But growth is certain (4:26–29). The outcome will be great (4:32).