John Nelson Darby expounds on Matthew 13, emphasizing that the Lord's ministry as a Sower is focused on sowing the word of God in hearts rather than seeking fruit from Israel. He highlights the different responses to the word, illustrating how understanding and connection with God are essential for producing fruit. The parables presented reveal the nature of the kingdom during Christ's absence, showing the mingling of good and evil and the eventual judgment that will separate them. Darby stresses that the true children of the kingdom are those born of the word, and the ultimate purpose of Christ's sacrifice is to redeem His people, the treasure hidden in the field. The sermon concludes with the assurance of God's judgment and the glory that awaits the righteous.