"Eat not of that on which Allah's name has not been pronounced" - that he said: "The idolaters argued with them and said: 'Whatever Allah kills you do not eat, and whatever you kill you eat!" (Using translation from Nasāʾī 4437)  

فِي قَوْلِهِ تَعَالَى {§وَلَا تَأْكُلُوا مِمَّا لَمْ يُذْكَرِ اسْمُ اللهِ عَلَيْهِ} [الأنعام 121] قَالَ «خَاصَمَهُمُ الْمُشْرِكُونَ» قَالُوا مَا ذَبَحَ اللهُ لَا تَأْكُلُوهُ وَمَا ذَبَحْتُمْ أَنْتُمْ أَكَلْتُمُوهُ