Introduction
The Just Judge will settle scores on the Day of Resurrection for one who was wronged with the one who wronged him, so that there will be no scores left unsettled. Allah, may He be Glorified and Exalted, says (interpretation of the meaning), "You O Muhammad will surely die, and they too will die; then on the Day of Resurrection, you will all dispute before your Lord." (al-Zumar 39:30-31)

Abu Hurayrah (may Allah be pleased with him) narrated that the Messenger of Allah (blessings and peace of Allah be upon him) said, “Rights will certainly be restored to all creatures on the Day of Resurrection, until even the hornless sheep will settle its score with the horned one.” (Muslim) It was narrated that Abu Hurayrah (may Allah be pleased with him) said, "The Messenger of Allah (blessings and peace of Allah be upon him) said, 'Whoever strikes someone with a whip wrongfully, the score will be settled with him on the Day of Resurrection.” (Al-Bukhari in al-Adab al-Mufrad, al-Bazzar, al-Tabarani; da‘if)

11.1. How scores will be settled on the Day of Resurrection
It was narrated that Abu Hurayrah (may Allah be pleased with him) said, "The Messenger of Allah (blessings and peace of Allah be upon him) said, 'Whoever wronged his brother with regard to his honour or anything else, let him seek his forgiveness today, before there will be no dinar and no dirham, and if he has any righteous deeds to his credit, they will be taken from him, commensurate with the wrong that he did, and if he does not have any good deeds to his credit, some of the bad deeds of his companion will be taken and added to his burden.'" (Al-Bukhari)

Al-Khattabi said, “What is meant by the taking of good deeds and bad deeds is that the reward for good deeds will be given to the one with the grievance, and the punishment for bad deeds will be given to the wrongdoer in return for the wrong he did.”

Abu Hurayrah (may Allah be pleased with him) narrated that the Messenger of Allah (blessings and peace of Allah be upon him) said, “Do you know what bankrupt means?” They said: The one who is bankrupt among us is the one who has no money or wealth. He said: “The one who is bankrupt among my ummah is the one who will come on the Day of Resurrection with prayer, fasting and zakah, but he will come having insulted this one, slandered that one, consumed the wealth of this one, shed the blood of that one and beaten this one. They will each be given from his good deeds, and if his good deeds run out before the scores have been settled, some of their bad deeds will be taken and cast upon him, then he will be thrown into Hell.” (Muslim).

11.2. The seriousness of bloodshed
‘Abdullah ibn Mas‘ud (may Allah be pleased with him) narrated that the Prophet (blessings and peace of Allah be upon him) said, “A man will come, holding another man by the hand and saying: ‘O Lord, this man killed me.’ Allah will say to him: ‘Why did you kill him?’ He will say: ‘I killed him so that the glory would be to You.’ Allah will say: ‘Verily, it is for Me.’ Then a man will come, holding another man by the hand and saying: ‘This man killed me.’ Allah will say to him: ‘Why did you kill him?’ He will say: ‘So that the glory would be to So and so.’ Allah will say: ‘It is not for So and so.’ So his sin of killing will be confirmed.” (al-Nasa’i, al-Tabarani, al-Bayhaqi; sahih)

Because bloodshed is such a serious matter, it will be the first matter concerning which judgement is passed among people. ‘Abdullah ibn Mas‘ud (may Allah be pleased with him) narrated that the Prophet (blessings and peace of Allah be upon him) said, “The first matter concerning which judgement will be passed among the people on the Day of Resurrection will be bloodshed.” (Al-Bukhari, Muslim)

Ibn Hajar said, “This hadith highlights the seriousness of bloodshed, because starting with something indicates that it is the most important. The greater the harm that results and the greater the benefits that are lost, the greater the sin is; killing a human being is especially grievous in that regard.”

He also said, "This is not contradicted by the marfu‘ hadith of Abu Hurayrah, ‘The first thing for which a person will be brought to account on the Day of Resurrection will be his prayer’ (Abu Dawud, al-Nasa’i, Ibn Majah, Ahmad; sahih)… because the first hadith is to be understood as referring to what has to do with people’s interactions, whereas the second hadith has to do with worshipping the Creator. Al-Nasa’i reconciled between the two hadiths in his report of the hadith of Ibn Mas‘ud, the wording of which is, 'The first thing for which a person will be brought to account is his prayer, and the first matter concerning which scores will be settled between people is bloodshed.'" (Al-Nasa’i, Muhammad ibn Nasr, Abu Ya‘la; sahih)

Ibn Baz said, "This is indicative of how serious the issue of bloodshed is, and that the first matter concerning which scores will be settled among people will be bloodshed, because of the rights and duties between them. This is a warning against shedding blood unlawfully and transgressing against people. The believer must be aware of transgressing against people and shedding blood unlawfully, for the crime of murder is very serious. Allah, may He be Glorified and Exalted, says (interpretation of the meaning), 'But whoever kills a believer deliberately, his punishment will be hell, to abide therein forever; Allah will be angry with him, and will curse him, and will prepare for him a grievous punishment.' (al-Nisa’ 4:93) And in the hadith, the Prophet (blessings and peace of Allah be upon him) said, 'A man will still have a chance of forgiveness unless he kills somebody unlawfully.'" (Al-Bukhari)

11.3. Animals will settle scores with one another
Allah, may He be Glorified and Exalted, says (interpretation of the meaning), "And when the wild beasts are gathered." (al-Takwir 81:5) Al-Shawkani said, “The word translated here as wild beasts refers to wild land animals. What is meant by are gathered is after the resurrection, so that they may settle scores with one another. Hence the hornless animal will settle its scores with the horned animal.”

Abu Hurayrah (may Allah be pleased with him) narrated that the Messenger of Allah (blessings and peace of Allah be upon him) said, “Rights will certainly be restored to all creatures on the Day of Resurrection, until even the hornless sheep will settle its score with the horned one.”

11.4. When will the believers settle scores with one another?
Abu Sa‘id al-Khudri (may Allah be pleased with him) narrated that the Messenger of Allah (blessings and peace of Allah be upon him) said, “When the believers have been saved from the fire, they will be detained at a bridge between Paradise and Hell, and they will settle the scores that were between them in this world until, when they are purified and cleansed, permission will be given for them to enter Paradise. By the One in Whose hand is the soul of Muhammad, one of them will recognise his dwelling in Paradise more readily than he recognises his dwelling in this world.” (al-Bukhari)