Translation by Constance Garnett.
Online version here

Translation by Larissa Volokhonsky and Richard Pevear

The doctor came out of the room again, muffled in his fur coat and with his cap on his head. His face looked almost angry and disgusted, as though he were afraid of getting dirty. He cast a cursory glance round the passage, looking sternly at Alyosha and Kolya as he did so. Alyosha waved from the door to the coachman, and the carriage that had brought the doctor drove up. The captain darted out after the doctor, and, bowing apologetically, stopped him to get the last word. The poor fellow looked utterly crushed; there was a scared look in his eyes.
“Your Excellency, your Excellency… is it possible?” he began, but could not go on and clasped his hands in despair. Yet he still gazed imploringly at the doctor, as though a word from him might still change the poor boy’s fate.
“I can’t help it, I am not God!” the doctor answered offhand, though with the customary impressiveness.
“Doctor… your Excellency… and will it be soon, soon?”
“You must be prepared for anything,” said the doctor in emphatic and incisive tones, and dropping his eyes, he was about to step out to the coach.

The doctor was just coming out of the room, already wrapped up in his fur coat and with his hat on his head. His face was almost angry and squeamish, as if he were afraid of dirtying himself on something. He gave a cursory look around the entryway and glanced sternly at Alyosha and Kolya. Alyosha waved to the coachman from the doorway, and the carriage that had brought the doctor drove up to the front door. The captain rushed out after the doctor and, bending low, almost writhing before him, stopped him to get his final word. The poor man looked completely crushed, his eyes were frightened.
“Your Excellency, your Excellency . . . can it be. . . ?” he began, and could not finish, but simply clasped his hands in despair, though still making a last plea to the doctor with his eyes, as if a word from the doctor now might indeed change the poor boy’s sentence.
“What can I do? I am not God,” the doctor replied in a casual, though habitually imposing, voice.
“Doctor . . . your Excellency . . . and will it be soon, soon?”
“Be pre-pared for any-thing,” the doctor pronounced, emphasizing each syllable, and, lowering his eyes, he himself prepared to step across the threshold to the carriage.

Translation by Constance Garnett.
Online version here

Translation by Larissa Volokhonsky and Richard Pevear

and highly prizing his flat, dull and always gleefully complacent German wit. The old man was fond of making jokes.
“Oh, yes, that’s what I say,” he went on stubbornly. “One head is good, but two are much better, but he did not meet another head with wits, and his wits went. Where did they go? I’ve forgotten the word.” He went on, passing his hand before his eyes, “Oh, yes, spazieren.”*
“Wandering?”
“Oh, yes, wandering, that’s what I say. Well, his wits went wandering and fell in such a deep hole that he lost himself. And yet he was a grateful and sensitive boy. Oh, I remember him very well, a little chap so high, left neglected by his father in the back yard, when he ran about without boots on his feet, and his little breeches hanging by one button.”
A note of feeling and tenderness suddenly came into the honest old man’s voice. Fetyukovitch positively started, as though scenting something, and caught at it instantly.
“Oh, yes, I was a young man then…. I was… well, I was forty-five then, and had only just come here. And I was so sorry for the boy then; I asked myself why shouldn’t I buy him a pound of… a pound of what? I’ve forgotten what it’s called. A pound of what children are very fond of, what is it, what is it?” The doctor began waving his hands again. “It grows on a tree and is gathered and given to everyone…”
“Apples?”
“Oh, no, no. You have a dozen of apples, not a pound…. No, there are a lot of them, and call little. You put them in the mouth and crack.”
“Nuts?”
“Quite so, nuts, I say so.” The doctor repeated in the calmest way as though he had been at no loss for a word. “And I bought him a pound of nuts, for no one had ever bought the boy a pound of nuts before. And I lifted my finger and said to him, ‘Boy, Gott der Vater.’ He laughed and said, ‘Gott der Vater’… ‘Gott der Sohn.’ He laughed again and lisped ‘Gott der Sohn.’ ‘Gott der heilige Geist.’ Then he laughed and said as best he could, ‘Gott der heilige Geist.’ I went away, and two days after I happened to be passing, and he shouted to me of himself, ‘Uncle, Gott der Vater, Gott der Sohn,’ and he had only forgotten ‘Gott der heilige Geist.’ But I reminded him of it and I felt very sorry for him again. But he was taken away, and I did not see him again. Twenty-three years passed. I am sitting one morning in my study, a white-haired old man, when there walks into the room a blooming young man, whom I should never have recognised, but he held up his finger and said, laughing, ‘Gott der Vater, Gott der Sohn, and Gott der heilige Geist. I have just arrived and have come to thank you for that pound of nuts, for no one else ever bought me a pound of nuts; you are the only one that ever did.’ And then I remembered my happy youth and the poor child in the yard, without boots on his feet, and my heart was touched and I said, ‘You are a grateful young man, for you have remembered all your life the pound of nuts I bought you in your childhood.’ And I embraced him and blessed him. And I shed tears. He laughed, but he shed tears, too… for the Russian often laughs when he ought to be weeping. But he did weep; I saw it. And now, alas!…”
“And I am weeping now, German, I am weeping now, too, you saintly man,” Mitya cried suddenly.

* Promenading.

prizing all the more his potato-thick and always happily self-satisfied German wit. And the dear old man loved to be witty.
“Oh, y-yes, that’s what I am saying,” he picked up stubbornly, “two heads are much better than one head. But no one came to him with another head, and he even sent his own head for . . . How do you say, where did he send it? This word—-where he sent his head-—I’ve forgotten,” he went on waving his hand in front of his eyes, “ah, yes, spazieren.”
“For a walk?”
“Yes, for a walk, that’s what I am saying. So his head went for a walk and came to some deep place where it lost itself. And yet he was a grateful and sensitive young man, oh, I remember him still as such a tiny boy, left alone in his father’s backyard, where he was running in the dirt without any shoes and just one button on his little britches.”
A certain note of sensitivity and emotion was suddenly heard in the honest old man’s voice. Fetyukovich fairly started, as if anticipating something, and instantly hung on to it.’
“Oh, yes, I myself was a young man then. . . I was. . . well, yes, I was then forty-five years old, and had just come here. And I felt pity for the boy then, and I asked myself: why shouldn’t I buy him a pound of. . . well, yes, a pound of what? I forget what it‘s called. . . a pound of what children like so much, what is it—well, what is it. . . ?” the doctor again waved his hand. “It grows on a tree, they gather it and give it to everyone. . .”
“Apples?”
“Oh, n-n-no! A pound, a pound——apples come in dozens, not pounds. . . no, there are many of them, and they are all small, you put them in the mouth and cr-r-rack…!”
“Nuts?”
“Well, yes, nuts, that is what I am saying,” the doctor confirmed in the calmest way, as if he had not even been searching for the word, “and I brought the boy a pound of nuts, because no one had ever yet brought the boy a pound of nuts, and I held up my finger and said to him: ‘Boy! Gott der Vater,’ and he laughed and said, ‘Gott der Vater.’ ‘Gott der Sohn.’ Again he laughed and said, ‘Gott der Sohn.’ ‘Gott der heilige Geist.’ Then he laughed again and said as well as he could, ‘Gott der heilige Geistf’ And I left. Two days later I was passing by and he called out to me himself: ‘Hey, uncle, Gott der Vater, Gott der Sohn,’ only he forgot ‘Gott der heilige Geist,’ but I reminded him, and again I felt great pity for him. But he was taken away, and I did not see him anymore. And now after twenty-three years have gone by, I am sitting one morning in my study, and my head is already gray, and suddenly a blossoming young man comes in, whom I would never have recognized, but he held up his finger and said, laughing: ‘Gott der Vater, Gott der Sohn, und Gott der heilige Geist! I’ve just arrived, and have come to thank you for that pound of nuts; for no one bought me a pound of nuts before; you are the only one who ever bought me a pound of nuts.’ And then I remembered my happy youth, and a poor boy in the yard without any shoes, and my heart turned over, and I said: ‘You are a grateful young man, for all your life you have remembered that pound of nuts I brought you in your childhood.’ And I embraced him and blessed him. And I wept, He was laughing, but he also wept . . . for a Russian quite often laughs when he ought to weep. But he wept, too, I saw it. And now, alas . . . !”
“And I’m weeping now, too, German, I’m weeping now, too, you man of God!” Mitya suddenly cried from his place.