Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
quran:5:30

And his soul permitted to him the murder of his brother, so he killed him and became among the losers.  

Then his soul prompted him, it seduced him, to slay his brother, so he slew him and became one of the losers, by slaying him. And he did not know what to do with him, because he was the first of the Children of Adam to die on earth, and so he carried him on his back.
القرآن:٥:٣٠

فَطَوَّعَتْ لَهُ نَفْسُهُ قَتْلَ أَخِيهِ فَقَتَلَهُ فَأَصْبَحَ مِنَ الْخَاسِرِينَ  

{فطوَّعت} زينت {له نفسه قتل أخيه فقتله فأصبح} فصار {من الخاسرين} بقتله ولم يدرِ ما يصنع به لأنه أول ميت على وجه الأرض من بني آدم فحمله على ظهره.