كتاب الصيد والذبائح
Read the English translation first, with the original Arabic directly underneath.
It was narrated that 'Adiyy bin Hatim said:
"I asked the Messenger of Allah: 'I release my dog. He said: 'If you release your dog and mention the name of Allah, then eat. But it he has eaten some of it, the do not eats, for the caught it for himself. If you release your dog then you find another dog with it, then do not eat, for you said the name of Allah over your dog, and not over any other.""
إِذَا أَرْسَلْتَ كَلْبَكَ فَسَمَّيْتَ فَكُلْ وَإِنْ أَكَلَ مِنْهُ فَلاَ تَأْكُلْ فَإِنَّمَا أَمْسَكَ عَلَى نَفْسِهِ وَإِذَا أَرْسَلْتَ كَلْبَكَ فَوَجَدْتَ مَعَهُ غَيْرَهُ فَلاَ تَأْكُلْ فَإِنَّكَ إِنَّمَا سَمَّيْتَ عَلَى كَلْبِكَ وَلَمْ تُسَمِّ عَلَى غَيْرِهِ