A Hadith states that the Prophet said,

«مَا مِنْ ذَنْبٍ أَجْدَرُ أَنْ يُعَجِّلَ اللهُ عُقُوبَتَهُ فِي الدُّنْيَا مَعَ مَا يَدَّخِرُ لِصَاحِبهِ فِي الْآخِرَةِ مِنَ الْبَغْيِ وَقَطِيعَةِ الرَّحِم»

(There is no sin that is more worthy of Allah hastening its punishment in this life, in addition to what He has in store for its offender in the Hereafter, more than transgression and cutting the relations of the womb.) The act of Qabil included both of these. We are Allah's and to Him is our return.

﴿مِنْ أَجْلِ ذلِكَ كَتَبْنَا عَلَى بَنِى إِسْرَءِيلَ أَنَّهُ مَن قَتَلَ نَفْساً بِغَيْرِ نَفْسٍ أَوْ فَسَادٍ فِى الاٌّرْضِ فَكَأَنَّمَا قَتَلَ النَّاسَ جَمِيعاً وَمَنْ أَحْيَـهَا فَكَأَنَّمَا أَحْيَا النَّاسَ جَمِيعاً وَلَقَدْ جَآءَتْهُمْ رُسُلُنَا بِالّبَيِّنَـتِ ثُمَّ إِنَّ كَثِيراً مِّنْهُمْ بَعْدَ ذلِكَ فِى الاٌّرْضِ لَمُسْرِفُونَ - إِنَّمَا جَزَآءُ الَّذِينَ يُحَارِبُونَ اللَّهَ وَرَسُولَهُ وَيَسْعَوْنَ فِى الاٌّرْضِ فَسَاداً أَن يُقَتَّلُواْ أَوْ يُصَلَّبُواْ أَوْ تُقَطَّعَ أَيْدِيهِمْ وَأَرْجُلُهُم مِّنْ خِلَـفٍ أَوْ يُنفَوْاْ مِنَ الاٌّرْضِ ذَلِكَ لَهُمْ خِزْىٌ فِى الدُّنْيَا وَلَهُمْ فِى الاٌّخِرَةِ عَذَابٌ عَظِيمٌ - إِلاَّ الَّذِينَ تَابُواْ مِن قَبْلِ أَن تَقْدِرُواْ عَلَيْهِمْ فَاعْلَمُواْ أَنَّ اللَّهَ غَفُورٌ رَّحِيمٌ ﴾

(32. Because of that, We ordained for the Children of Israel that if anyone killed a person not in retaliation of murder, or (and) to spread mischief in the land - it would be as if he killed all mankind, and if anyone saved a life, it would be as if he saved the life of all mankind. And indeed, there came to them Our Messengers with Al-Bayyinat, even then after that many of them continued to exceed the limits in the land!) (33. The recompense of those who wage war against Allah and His Messenger and do mischief in the land is only that they shall be killed or crucified, or their hands and their feet be cut off on opposite sides, or be exiled from the land. That is their disgrace in this world, and a great torment is theirs in the Hereafter.) (34. Except for those who (having fled away and then) came back (as Muslims) with repentance before they fall into your power; in that case, know that Allah is Oft-Forgiving, Most Merciful.)