In The Metamorphosis by Franz Kafka, why did Gregor's father throw apples at him and what is their symbolic meaning?

Grigor's father does not throw apples to Gregor, but at him. This is not only because he is repelled by him, but because he starts to think of him as being actively dangerous. This is after Gregor has inadvertently succeeded into scaring his mother into a faint, when she and his sister went into his room to start clearing out his things. Gregor's father has shown himself unsympathetic to Gregor from the first - even when he was still in human form, and doubly so once he takes on his new monstrous appearance. He instantly assumes the worst when he finds his wife in a fainting fit and despite Grete's pleas, does not hesitate to start pelting Gregor with apples. In fact, he has already been knocking Gregor about before this incident.

The apple has often been associated with symbolic meaning. Going back to the story told in Genesis in the Bible, when Adam and Eve ate the apple of knowledge and lost their primal innocence, it has often been used as a somewhat negative symbol: of guilt, sin and suffering, even although on the face of it it is a rich and tempting fruit. It is when his father flings these apples at him, trying to actually hurt him (and succeeding) that the irrevocable change in Gregor's situation really hits home, in this scene of violence and chaos. He has most unintentionally scared his mother and his father is now attacking him. Grete alone still appears as an ally but she too will eventually repudiate him. Moreover, one of the apples injures him quite seriously when lodging in his back. From this point on, he is less able to function physically; he can no longer do much for himself. It marks the start of his long decline which results in his inevitable death. 

What page in The Metamorphosis does Gregor's father throw an apple at him?

Depending on the edition of "The Metamorphosis" that you have, the page in which Gregor Samsa's father throws an apple at him will vary. Since "The Metamorphosis" is a canonical and widely-studied piece of fiction, the story has been published a significant number of times in many different languages, both as a stand-alone story and in several collections of stories.

The edition referred to here is the Schocken Books printing of Franz Kafka: The Complete Stories. Here, "The Metamorphosis" is published amongst the rest of Kafka's shorter works of fiction. In this edition, Gregor's father throws the apple on page 122. The passage reads, "the small red apples rolled about the floor as if magnetized and cannoned into each other. An apple thrown without much force grazed Gregor's back and glanced off harmlessly. But another following immediately landed right on his back and sank in" (122).

There is a darkly comic element to this violence; apples certainly aren't considered to be weapons in daily life, yet it is an apple thrown by Gregor's father that will ultimately be his demise. The apple becomes wedged deeply into Gregor's back, and Gregor becomes immobilized and weakened. His grotesque and horrid appearance frightened his family significantly, leading to the assault with the apples. Gregor is ultimately confined to his room while his family continues their life on the other side of the door, further increasing the crippling alienation that had plagued him since his transformation.

What page in The Metamorphosis does Gregor's father throw an apple at him?

At the end of chapter two (page 64), in the story “The Metamorphosis,” Gregor’s father begins throwing apples at Gregor. Although Gregor lived as a bug with his family for quite some time (by this point in the story), his family still feared him and believed that his actions could cause harm.

Due to their fear, Gregor’s father tried to force Gregor to retreat back to his room and leave his mother and sister alone. Although his mother and sister had been trying to help him by removing the furniture in his room, Gregor did not want to lose the belongings that brought a hope of transforming back into a human. As Gregor's thoughts reveal:

"Nothing was to be removed; everything must remain. In his condition he couldn’t function without the beneficial influences of his furniture."

As a result, he accidentally scared his mother and then, instinctively followed her out of his room to try to help her. Regardless of his good intentions, his father’s fear caused him to retaliate and throw apples at his son.

How does Gregor's father react to his appearance in The Metamorphosis?

When Gregor's father first sees him, he has a "hostile expression" on his face. He "clenched his fist, as if to drive Gregor back into the room, then looked uncertainly around the living room, shielded his eyes with his hands, and sobbed with heaves of his powerful chest." The scene, of course, is utterly tumultuous. Gregor's manager from work is there, and Gregor is feeling absolutely terrible about letting down his family.  He recognizes that he cannot allow the manager to leave, so he tries to keep very calm and explain the situation, promising that he will come to work shortly.  It is not going well, and then the coffee spills. Gregor cannot stop himself from snapping his jaws in the air, a motion that upsets everyone even further, including his father, who Gregor says has been "relatively calm until now."  At this point, his father begins to stamp his feet and hiss at Gregor, which Gregor finds totally horrifying and threatening. 

Pitilessly his father came on, hissing like a wild man. . . [and] at any minute the cane in his father's hand threatened to come down on his back or his head with a deadly blow.

His father forces Gregor back into his room, physically shoving him when he seems to get stuck in the door.

Why did Gregor's father throw apples in The Metamorphosis?

While Gregor's father is at work at his job at the bank, Gregor, now an insect, follows his sister, Grete, into the dining room, which frightens and upsets her. Gregor realizes that he is causing a commotion and that his intentions have been misunderstood as hostile. He has no way of communicating to Grete that he means no harm, so he retreats back to his room, trying to show that he is not aggressive.

When his father returns from work, he finds the household in an uproar over Gregor. Ever since Gregor turned into an insect, the disciplinarian father has decided that his adult son needs to be controlled with a firm hand. He feels that the women do not do this correctly. Therefore, without thinking much about what he is doing, he fills his pockets with apples from the dining room and starts flinging them hard at Gregor to teach him a lesson not to leave his room.

One of the apples gets stuck in Gregor's back in a very painful way. Meanwhile, his mother and sister scream at the father and try to pull him away, fearing that he will kill Gregor.

Gregor is badly injured, but everyone is afraid to pull the apple out. Even his father feels some remorse, as he recognizes that although Gregor is an insect, he is still a family member.

What happens when Gregor's father throws an apple at him in The Metamorphosis?

After collecting a number of small, red apples from a fruit bowl, Gregor's father begins throwing them at Gregor.

Finally, unable to scurry away from his attacking father, an apple hits him very hard in the back. It lodges there and causes Gregor excruciating pain. No one does anything to help poor Gregor, and the apple stays imbedded in his back. It continues to cause him much pain, and Gregor's situation get worse and worse.

In a meager attempt to finally accept the now suffering and almost immobile, transformed Gregor into the family, the door to his room is left open and Gregor can peer from his darkness into the living room where his family might now and then gather.

In The Metamorphosis, how does Gregor's father's violent action of throwing apples affirm Gregor's inclusion within the family?

One could argue that this violent action has the exact opposite intention. Far from wanting to include Gregor in the family group, his father wants to exclude him from it altogether. He no longer sees Gregor as his son but as some kind of monster, something that belongs in a zoo or a circus, not in the family home. When Gregor's father throws fruit at him, it's an immediate response to what he wrongly thinks is an attack by Gregor on his mother. In the heat of the moment, Gregor's father isn't thinking about inclusion; he just wants to send this revolting creature scurrying away so he can no longer do any harm to anyone.

At the same time, however, Gregor's father is behaving like someone in his position would be expected to behave towards a disobedient son. Physical methods of chastisement against children were widely considered acceptable in those days, and so Gregor's father violently throwing fruit at his son could be seen as an acknowledgement, albeit a rather unusual one, that Gregor is still, despite his shocking appearance, his own flesh and blood.