Genèse 42:21

And they said, a man to his brother, In truth we are guilty concerning our brother, when we saw the distress of his soul, when be entreated us, and we would not hearken to him; therefore hath this affliction come upon us.

IN THAT WE SAW THE DISTRESS OF HIS SOUL, WHEN HE IMPLORED US. It is obvious that the brothers now considered their display of cruelty towards Joseph as deserving of a greater punishment than the sale itself since it was their blood-brother who was imploring and prostrating himself before them and they remained unmoved. Scripture, however, did not relate there [that Joseph implored them at the time of the sale], either because it is naturally understood that a person would implore his brothers when falling into their grip when their intention is to harm him, swearing by the life of his father, and doing all that is possible to save himself from death. It may be the desire of Scripture to speak only briefly of their sin, or it is possible that it is characteristic of Scripture to speak briefly about a matter in one place, and to elaborate on it in another place.
Now Reuben answered them by saying: “Now I already told you at the time that the event took place that you should not sin against him for he is only a lad, and only on account of his youth did he sin against you, and it is therefore fitting for you to gloss over the sins of his youth. And now, his blood also, together with the display of cruelty which you mention, is required.” Perhaps the explanation of the phrase, his blood also, may be: “Even though you have not killed him, G-d will require his blood of you, and it will be accounted to you as if you spilled his blood since he was sold as a permanent slave, for it is possible that being a darling child, unused to work, he died.”
Our Rabbis have expounded “The expression, ‘Also’ his blood, implies his blood and the blood of his aged father.”

הצרה הזאת, tit for tat. We threw Joseph into a pit, now we have been thrown into jail.

בהתחננו אלינו ולא שמעבו. This made us guilty of being cruel against our brother, even though we considered him halachically in the category of a רודף, someone threatening us. We should have reacted with pity once he started pleading with us. Now, we are being punished by being treated cruelly ourselves by the ruler of this land.

ויאמרו, after Joseph had finished speaking with them and had left, the interpreter who had acted to preserve the impression that Joseph did not understand Hebrew also left the room where the encounter between Joseph and his brothers had taken place. In the absence of the interpreter the brothers acknowledged their sin against Joseph, seeing in their incarceration and in their position as accused, G’d’s punishment for their conduct against Joseph. They knew that they had been discriminated against by Joseph, knowing that they had been subjected to a far more intense questioning than other travelers who had come to Egypt to buy food. This is why they connected their present predicament to their behaviour against Joseph. However, they saw the nature of their sin not in their basic attitude to Joseph but

בהתחננו אלינו¸ their turning a deaf ear to Joseph’s pleas for mercy after he had been thrown into the pit. Joseph had started pleading already when they stripped him of the coloured coat his father had had made for him especially. The entire episode is described in detail by the Torah to teach the reader that if and when apparently undeserved troubles befall him, that he is to examine his past deeds to find out what sin, intentional or unintentional, could have caused G’d to bring this to his attention in such a manner so that he would repent his error. He is to exploit his troubles to ask G’d for forgiveness for his wrongdoing. [even if the major act of penitence has to be performed toward the person against whom he had sinned and from whom he must ask for a pardon. Ed.]