“Spare him!” echoed Zoroaster scornfully.  “He is almost dead now—­why should I spare him?”

“For my sake, beloved,” answered Nehushta, with a sudden and passionate gesture of entreaty.  “He is the king—­he speaks truth; if he says he will not harm you, trust him.”

“If I slay thee not, swear thou wilt not harm me nor Nehushta,” said Zoroaster, removing one knee from the chest of his adversary.

“By the name of Auramazda,” gasped Darius, “I will not harm thee nor her.”

“It is well,” said Zoroaster.  “I will let thee go.  And as for taking her to be thy wife, thou mayest ask her if she will wed thee,” he added.  He rose and helped the king to his feet.  Darius shook himself and breathed hard for a few minutes.  He felt his limbs as a man might do who had fallen from his horse, and then he sat down upon the chair, and broke into a loud laugh.

Darius was well known to all Persia and Media before the events of the last two months, and such was his reputation for abiding by his promise that he was universally trusted by those about him.  Zoroaster had known him also, and he remembered his easy familiarity and love of jesting, so that even when he held the king at such vantage that he might have killed him by a little additional pressure of his weight, he felt not the least hesitation in accepting his promise of safety.  But remembering what a stake had been played for in the desperate issue, he could not join in the king’s laugh.  He stood silently apart, and looked at Nehushta who leaned back against the tent-pole in violent agitation; her hands wringing each other beneath her long sleeves, and her eyes turning from the king to Zoroaster, and back again to the king, in evident distress and fear.

“Thou hast a mighty arm, Zoroaster,” cried Darius, as his laughter subsided, “and thou hadst well-nigh made an end of the Great King and of Persia, Media, Babylon and Egypt in thy grip.”

“Let the king pardon his servant,” answered Zoroaster, “if his knee was heavy and his hand strong.  Had not the king slipped upon the spilt wine, his servant would have been thrown down.”

“And thou wouldst have been crucified at dawn,” added Darius, laughing again.  “It is well for thee that I am Darius and not Cambyses, or thou wouldst not be standing there before me while my guards are gossiping idly in the road.  Give me a cup of wine since thou hast spared my life!” Again the king laughed as though his sides would break.  Zoroaster hastily filled another goblet and offered it, kneeling before the monarch.  Darius paused before he took the cup, and looked at the kneeling warrior’s pale proud face.  Then he spoke and his voice dropped to a less mirthful key, as he laid his hand on Zoroaster’s shoulder.

“I love thee, prince,” he said, “because thou art stronger than I; and as brave and more merciful.  Therefore shalt thou stand ever at my right hand and I will trust thee with my life in thy hand.  And in pledge hereunto I put my own chain of gold about thy neck, and I drink this cup to thee; and whosoever shall harm a hair of thine head shall perish in torments.”