The Prophet ﷺ forbade that the food of two people who were rivalling on another should be eaten Abu Dawud said: Most of those who narrated it from Jarir did not mention the name of Ibn Abbas. Harun al-Nahwi mentioned Ibn 'Abbas in it, and Hammad bin Zaid did not mention Ibn 'Abbas.  

سَمِعْتُ عِكْرِمَةَ يَقُولُ كَانَ ابْنُ عَبَّاسٍ يَقُولُ إِنَّ النَّبِيَّ ﷺ نَهَى عَنْ طَعَامِ الْمُتَبَارِيَيْنِ أَنْ يُؤْكَلَ