I'm writing in the thread for chapter 45 because I don't want to make forward references that would act as "spoilers" for first-time readers. If I've nonetheless chosen the wrong place to leave these remarks, I ask that one not delete them out of hand; please just move them elsewhere, or let me know, and give me some time to move them myself.
Some readers will recall Frank Herbert's interest in human beings' ability to find patterns. I've found one in Dune itself that seems more than chance can account for. The chapter numbers and summaries in this forum's posts have been quite helpful, and I'm grateful for moderator "Freakzilla's" care and effort in numbering the chapters and writing the summaries. The pattern of interest to me here concerns chapters 9, 18, 27, 36, and 45. I was alerted to the possibility of a pattern by the emphasis on the number 9 or IX in the Dune series. The pattern in these chapters is not an absolute one, but I think Herbert's readers will agree that an absolute pattern would be contrary to Herbert's likely opinions about patterns and absolutes.
In chapter 9, Yueh has given Paul a drug that would have put him to sleep. Paul has "palmed" the pill, thus using his hand in a way that in effect saves him from dying in his sleep. He seems to sleep but gets up and moves in time to avoid being pinned under his headboard's waves and killed by a hunter-seeker. He is not wearing his shield. He traps the hunter-seeker with his hand and thereby saves the life of the Fremen woman Mapes, who thus feels indebted to him but discharges her debt. She warns him of a traitor, whom we know to be Yueh. Paul realizes his peril and goes to warn his mother.
Chapter 18 begins with the Dirge for Jamis, which asks Jamis whether he moves "in a kind of sleep." In chapter 9, Paul did not tarry, but the maker of the Dirge says that Jamis did. Paul lived, but Jamis's "life is stolen." In chapter 18, we have not yet actually met Jamis, but we have met the Duke Leto. Leto is awake at a time when he might have been asleep. He is wearing his shield, but he leaves it off. Does Leto "move in a kind of sleep"? Like Paul, Leto encounters Mapes, but he is already too late to save her. Mapes warns him of a traitor, whom we know to be Yueh. Leto realizes his peril, but unlike Paul's hand, Leto's hand is slow. Paul stopped the hunter-seeker, but Leto does not stop Yueh's dart. Yueh did not put Paul to sleep, but he puts Leto to sleep. He has already sedated the house generators.
In chapter 27, Jessica, though not pinned under a headboard's waves, is buried under a wave of sand. No one puts her to sleep or destroys her, but she puts herself in a kind of sleep and helps to save herself. Paul has saved a Fremen woman by his well-trained hand; that Fremen woman incurred a debt to him and quickly discharged it. Now Paul finds, saves, and wakes his mother, and she wants to train the hands that saved her.
In chapters 9 and 27, Paul saved a servant woman and his mother, maintaining what he had already. In chapter 36, Paul gains a servant from her husband Jamis, whom Paul slew as Jamis tried to slay him; and Paul gains a wife from her father Liet, who was slain for having saved Paul.
In chapter 45, Paul gives himself a drug and moves in a kind of sleep. Had he tarried too long, his life would have been stolen, and he could have been counted a victim of his folly. Two women, the mother he saved and the wife he gained, wake him from his death-like sleep and save him.