Sunan an-Nasa'i, Volume 5, Book 37, Hadith 4020 (DarusSalam) ⓘ
It was narrated that 'Abdullah said: "I asked the Messenger of Allah [SAW], which sin is most grievous?" He said: "Shirk, setting up a rival to Allah, committing adultery with your neighbor's wife, and killing your child for fear of poverty, and that he may eat with you." Then 'Abdullah recited the Verse: "And those who invoke not any other Ilah (god) along with Allah."
أَخْبَرَنَا عَبْدَةُ، قَالَ أَنْبَأَنَا يَزِيدُ، قَالَ أَنْبَأَنَا شُعْبَةُ، عَنْ عَاصِمٍ، عَنْ أَبِي وَائِلٍ، عَنْ عَبْدِ اللَّهِ، قَالَ سَأَلْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم أَىُّ الذَّنْبِ أَعْظَمُ قَالَ " الشِّرْكُ أَنْ تَجْعَلَ لِلَّهِ نِدًّا وَأَنْ تُزَانِيَ بِحَلِيلَةِ جَارِكَ وَأَنْ تَقْتُلَ وَلَدَكَ مَخَافَةَ الْفَقْرِ أَنْ يَأْكُلَ مَعَكَ " . ثُمَّ قَرَأَ عَبْدُ اللَّهِ { وَالَّذِينَ لاَ يَدْعُونَ مَعَ اللَّهِ إِلَهًا آخَرَ } . قَالَ أَبُو عَبْدِ الرَّحْمَنِ هَذَا خَطَأٌ وَالصَّوَابُ الَّذِي قَبْلَهُ وَحَدِيثُ يَزِيدَ هَذَا خَطَأٌ إِنَّمَا هُوَ وَاصِلٌ وَاللَّهُ تَعَالَى أَعْلَمُ .
also referenced under: Hadith 4015 (Reference) & Book 37, Hadith 50 (In-Book)