Sermons that ‘follow the plan’ are most natural and effective when there is some kind of forward momentum in the text itself. So, for example, when preaching from Ruth 4, which traces Ruth’s descendants as far as King David, or when explaining the story of Jehosheba in 2 Kings 11 where the same royal line is nearly wiped out, it would make perfect sense to follow the unfolding plan to its fulfilment in the Lord Jesus Christ.