From "Manual of Muad'Dib" by the Princess Irulan

He has the Great Control , she thought.
Gurney's arm trembled against her neck. The point of the knife at her back moved with uncertainty.
"What you have not done," Paul said, "is heard my mother sobbing in the night over her lost Duke. You have not seen her eyes stab flame when she speaks of killing Harkonnens."
So he has listened , she thought. Tears blinded her eyes .
"What you have not done," Paul went on, "is remembered the lessons you learned in a Harkonnen slave pit. You speak of pride in my father's friendship! Didn't you learn the difference between Harkonnen and Atreides so that you could smell a Harkonnen trick by the stink they left on it? Didn't you learn that Atreides loyalty is bought with love while the Harkonnen coin is hate? Couldn't you see through to the very nature of this betrayal?"
"But Yueh?" Gurney muttered.
"The evidence we have is Yueh's own message to us admitting his treachery," Paul said. "I swear this to you by the love I hold for you, a love I will still hold even after I leave you dead on this floor."
Hearing her son, Jessica marveled at the awareness in him, the penetrating insight of his intelligence.
"My father had an instinct for his friends," Paul said. "He gave his love sparingly, but with never an error. His weakness lay in misunderstanding hatred. He thought anyone who hated Harkonnens could not betray him." He glanced at his mother. "She knows this. I've given her my father's message that he never distrusted her."
Jessica felt herself losing control, bit at her lower lip. Seeing the stiff formality in Paul, she realized what these words were costing him. She wanted to run to him, cradle his head against her breast as she never had done. But the arm against her throat had ceased its trembling; the knifepoint at her back pressed still and sharp.
"One of the most terrible moments in a boy's life," Paul said, "is when he discovers his father and mother are human beings who share a love that he can never quite taste. It's a loss, an awakening to the fact that the world is there and here and we are in it alone. The moment carries its own truth; you can't evade it. I heard my father when he spoke of my mother. She's not the betrayer, Gurney."
Jessica found her voice, said: "Gurney, release me." There was no special command in the words, no trick to play on his weaknesses, but Gurney's hand fell away. She crossed to Paul, stood in front of him, not touching him.
"Paul," she said, "there are other awakenings in this universe. I suddenly see how I've used you and twisted you and manipulated you to set you on a course of my choosing . . . a course I had to choose—if that's any excuse—because of my own training." She swallowed past a lump in her throat, looked up into her son's eyes. "Paul . . . I want you to do something for me: choose the course of happiness. Your desert woman, marry her if that's your wish. Defy everyone and everything to do this. But choose your own course. I . . . "
She broke off, stopped by the low sound of muttering behind her.
Gurney!
She saw Paul's eyes directed beyond her, turned.
Gurney stood in the same spot, but had sheathed his knife, pulled the robe away from his breast to expose the slick grayness of an issue stillsuit, the type the smugglers traded for among the sietch warrens.
"Put your knife right here in my breast," Gurney muttered. "I say kill me and have done with it. I've besmirched my name. I've betrayed my own Duke! The finest—"
"Be still!" Paul said.
Gurney stared at him.
"Close that robe and stop acting like a fool," Paul said. "I've had enough foolishness for one day."
"Kill me, I say!" Gurney raged.
"You know me better than that," Paul said. "How many kinds of an idiot do you think I am? Must I go through this with every man I need?"
Gurney looked at Jessica, spoke in a forlorn, pleading note so unlike him: "Then you, my Lady, please . . . you kill me."
Jessica crossed to him, put her hands on his shoulders. "Gurney, why do you insist the Atreides must kill those they love?" Gently, she pulled the spread robe out of his fingers, closed and fastened the fabric over his chest.
Gurney spoke brokenly; "But . . . I . . . "
"You thought you were doing a thing for Leto," she said, "and for this I honor you."
"My Lady," Gurney said. He dropped his chin to his chest, squeezed his eyelids closed against the tears.
"Let us think of this as a misunderstanding among old friends," she said, and Paul heard the soothers, the adjusting tones in her voice. "It's over and we can be thankful we'll never again have that sort of misunderstanding between us."
Gurney opened eyes bright with moisture, looked down at her.
"The Gurney Halleck I knew was a man adept with both blade and baliset," Jessica said. "It was the man of the baliset I most admired. Doesn't that Gurney Halleck remember how I used to enjoy listening by the hour while he played for me? Do you still have a baliset, Gurney?"
"I've a new one," Gurney said. "Brought from Chusuk, a sweet instrument. Plays like a genuine Varota, though there's no signature on it. I think myself it was made by a student of Varota's who . . ." He broke off. "What can I say to you, my Lady? Here we prattle about—"
"Not prattle, Gurney," Paul said. He crossed to stand beside his mother, eye to eye with Gurney. "Not prattle, but a thing that brings happiness between friends. I'd take it a kindness if you'd play for her now. Battle planning can wait a little while. We'll not be going into the fight till tomorrow at any rate."
"I . . . I'll get my baliset," Gurney said. "It's in the passage." He stepped around them and through the hangings.
Paul put a hand on his mother's arm, found that she was trembling.
"It's over, Mother," he said.
Without turning her head, she looked up at him from the corners of her eyes. "Over?"
"Of course. Gurney's . . . "
"Gurney? Oh . . . yes." She lowered her gaze.
The hangings rustled as Gurney returned with his baliset. He began tuning it, avoiding their eyes. The hangings on the walls dulled the echoes, making the instrument sound small and intimate.
Paul led his mother to a cushion, seated her there with her back to the thick draperies of the wall. He was suddenly struck by how old she seemed to him with the beginnings of desert-dried lines in her face, the stretching at the corners of her blue-veiled eyes.