Hadithcore
Sahih al-Bukhari, 7461
sahih

Narrated Ibn `Abbas:

The Prophet (ﷺ) stood before Musailama (the liar) who was sitting with his companions then, and said to him, "If you ask me for this piece (of palm-leaf stalk), even then I would not give it to you. You cannot avoid what Allah has ordained for you, and if you turn away from Islam, Allah will surely ruin you! "

حَدَّثَنَا أَبُو الْيَمَانِ، أَخْبَرَنَا شُعَيْبٌ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي حُسَيْنٍ، حَدَّثَنَا نَافِعُ بْنُ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ وَقَفَ النَّبِيُّ صلى الله عليه وسلم عَلَى مُسَيْلِمَةَ فِي أَصْحَابِهِ فَقَالَ ‏

‏ لَوْ سَأَلْتَنِي هَذِهِ الْقِطْعَةَ مَا أَعْطَيْتُكَهَا، وَلَنْ تَعْدُوَ أَمْرَ اللَّهِ فِيكَ، وَلَئِنْ أَدْبَرْتَ لَيَعْقِرَنَّكَ اللَّهُ ‏

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References2 variants
In-Book Reference
Book 97, Hadith 87
USC-MSA web (English) reference
Vol. 9, Book 93, Hadith 553 (deprecated numbering scheme)