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

Jamis could do anything . . . any unpredictable thing , she told herself. She wondered then if Paul had glimpsed this future, if he were reliving this experience. But she saw the way her son moved, the beads of perspiration on his face and shoulders, the careful wariness visible in the flow of muscles. And for the first time she sensed, without understanding it, the uncertainty factor in Paul's gift.
Paul pressed the fight now, circling but not attacking. He had seen the fear in his opponent. Memory of Duncan Idaho's voice flowed through Paul's awareness: "When your opponent fears you, then's the moment when you give the fear its own rein, give it the time to work on him. Let it become terror. The terrified man fights himself. Eventually, he attacks in desperation. That is the most dangerous moment, but the terrified man can be trusted usually to make a fatal mistake. You are being trained here to detect these mistakes and use them ."
The crowd in the cavern began to mutter.
They think Paul's toying with Jamis , Jessica thought. They think Paul's being needlessly cruel .
But she sensed also the undercurrent of crowd excitement, their enjoyment of the spectacle. And she could see the pressure building up in Jamis. The moment when it became too much for him to contain was as apparent to her as it was to Jamis . . . or to Paul.
Jamis leaped high, feinting and striking down with his right hand, but the hand was empty. The crysknife had been shifted to his left hand.
Jessica gasped.
But Paul had been warned by Chani: "Jamis fights with either hand ." And the depth of his training had taken in that trick en passant . "Keep the mind on the knife and not on the hand that holds it ," Gurney Halleck had told him time and again. "The knife is more dangerous than the hand and the knife can be in either hand ."
And Paul had seen Jamis' mistake: bad footwork so that it took the man a heartbeat longer to recover from his leap, which had been intended to confuse Paul and hide the knife shift.
Except for the low yellow light of the glowglobes and the inky eyes of the staring troop, it was similar to a session on the practice floor. Shields didn't count where the body's own movement could be used against it. Paul shifted his own knife in a blurred motion, slipped sideways and thrust upward where Jamis' chest was descending—then away to watch the man crumble.
Jamis fell like a limp rag, face down, gasped once and turned his face toward Paul, then lay still on the rock floor. His dead eyes stared out like beads of dark glass.
"Killing with the point lacks artistry ," Idaho had once told Paul, "but don't let that hold your hand when the opening presents itself ."
The troop rushed forward, filling the ring, pushing Paul aside. They hid Jamis in a frenzy of huddling activity. Presently a group of them hurried back into the depths of the cavern carrying a burden wrapped in a robe.
And there was no body on the rock floor.
Jessica pressed through toward her son. She felt that she swam in a sea of robed and stinking backs, a throng strangely silent.
Now is the terrible moment , she thought. He has killed a man in clear superiority of mind and muscle. He must not grow to enjoy such a victory .
She forced herself through the last of the troop and into a small open space where two bearded Fremen were helping Paul into his stillsuit.
Jessica stared at her son. Paul's eyes were bright. He breathed heavily, permitting the ministrations to his body rather than helping them.
"Him against Jamis and not a mark on him," one of the men muttered.
Chani stood at one side, her eyes focused on Paul. Jessica saw the girl's excitement, the admiration in the elfin face.
It must be done now and swiftly , Jessica thought.
She compressed ultimate scorn into her voice and manner, said: "Well-l-l, now—how does it feel to be a killer?"
Paul stiffened as though he had been struck. He met his mother's cold glare and his face darkened with a rush of blood. Involuntarily he glanced toward the place on the cavern floor where Jamis had lain.
Stilgar pressed through to Jessica's side, returning from the cave depths where the body of Jamis had been taken. He spoke to Paul in a bitter, controlled tone: "When the time comes for you to call me out and try for my burda, do not think you will play with me the way you played with Jamis."
Jessica sensed the way her own words and Stilgar's sank into Paul, doing their harsh work on the boy. The mistake these people made—it served a purpose now. She searched the faces around them as Paul was doing, seeing what he saw. Admiration, yes, and fear . . . and in some—loathing. She looked at Stilgar, saw his fatalism, knew how the fight had seemed to him.
Paul looked at his mother. "You know what it was," he said.
She heard the return to sanity, the remorse in his voice. Jessica swept her glance across the troop, said: "Paul has never before killed a man with a naked blade."
Stilgar faced her, disbelief in his face.
"I wasn't playing with him," Paul said. He pressed in front of his mother, straightening his robe, glanced at the dark place of Jamis' blood on the cavern floor. "I did not want to kill him."
Jessica saw belief come slowly to Stilgar, saw the relief in him as he tugged at his beard with a deeply veined hand. She heard muttering awareness spread through the troop.
"That's why y' asked him to yield," Stilgar said. "I see. Our ways are different, but you'll see the sense in them. I thought we'd admitted a scorpion into our midst." He hesitated, then: "And I shall not call you lad the more."
A voice from the troop called out: "Needs a naming, Stil."
Stilgar nodded, tugging at his beard. "I see strength in you . . . like the strength beneath a pillar." Again he paused, then: "You shall be known among us as Usul, the base of the pillar. This is your secret name, your troop name. We of Sietch Tabr may use it, but none other may so presume . . . Usul."
Murmuring went through the troop: "Good choice, that . . . strong . . . bring us luck." And Jessica sensed the acceptance, knowing she was included in it with her champion. She was indeed Sayyadina.
"Now, what name of manhood do you choose for us to call you openly?" Stilgar asked.
Paul glanced at his mother, back to Stilgar. Bits and pieces of this moment registered on his prescient memory , but he felt the differences as though they were physical, a pressure forcing him through the narrow door of the present.
"How do you call among you the little mouse, the mouse that jumps?" Paul asked, remembering the pop-hop of motion at Tuono Basin . He illustrated with one hand.
A chuckle sounded through the troop.
"We call that one Muad'Dib," Stilgar said.
Jessica gasped. It was the name Paul had told her, saying that the Fremen would accept them and call him thus. She felt a sudden fear of her son and for him.
Paul swallowed. He felt that he played a part already played over countless times in his mind . . . yet . . . there were differences. He could see himself perched on a dizzying summit, having experienced much and possessed of a profound store of knowledge, but all around him was abyss.
And again he remembered the vision of fanatic legions following the green and black banner of the Atreides, pillaging and burning across the universe in the name of their prophet Muad'Dib.