What role does the preaching of the gospel play in the establishment of the Kingdom of God?

The parables in Mark 4 demonstrate that the preaching of the gospel is the means by which God establishes His Kingdom. Just as a farmer scatters seed without knowing how it grows, the faithful preaching of the gospel reaches hearts and fosters spiritual growth, with God orchestrating the increase. This process emphasizes that the preacher's role is to declare the truth boldly, trusting God to work in the hearts of listeners. Consequently, this reinforces the understanding that faith is a gift from God and that the results of gospel proclamation belong to His sovereign will.