Sunan al-Nasa'i
The Book of Fighting [The Prohibition of Bloodshed] — Hadith #4024
حَدَّثَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا سُفْيَانُ، قَالَ حَدَّثَنِي وَاصِلٌ، عَنْ أَبِي وَائِلٍ، عَنْ عَبْدِ اللَّهِ، قَالَ قُلْتُ يَا رَسُولَ اللَّهِ أَىُّ الذَّنْبِ أَعْظَمُ قَالَ " أَنْ تَجْعَلَ لِلَّهِ نِدًّا وَهُوَ خَلَقَكَ " . قُلْتُ ثُمَّ أَىٌّ قَالَ " أَنْ تَقْتُلَ وَلَدَكَ مِنْ أَجْلِ أَنْ يَطْعَمَ مَعَكَ " . قُلْتُ ثُمَّ أَىٌّ قَالَ " ثُمَّ أَنْ تُزَانِيَ بِحَلِيلَةِ جَارِكَ " .
“I said: ‘O Messenger of Allah, which sin is most grievous?’ He said: ‘Setting up a rival to Allah while it is He that created you.’ I said: ‘Then what?’ He said: ‘Killing your child so that he will not eat with you.’ I said: ‘Then what?’ He said: ‘Committing adultery with your neighbor’s wife.'”
Chain of Narration (Isnad)