Sahih 
Muslim
صحيح مسلم
24
                The Book of Gifts
كتاب الهبات
Chapter 1: It Is Disliked For A Man To Buy What He Gave In Charity From The One To Whom He Gave It
باب كَرَاهَةِ شِرَاءِ الإِنْسَانِ مَا تَصَدَّقَ بِهِ مِمَّنْ تَصَدَّقَ عَلَيْهِ 
Sahih Muslim 1620 b
This hadith has been narrated on the authority of Malik b. Anas with the same chain of transmitters but with this addition
" Don't buy that even if he gives you for one dirham."وَحَدَّثَنِيهِ زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا عَبْدُ الرَّحْمَنِ، - يَعْنِي ابْنَ مَهْدِيٍّ - عَنْ مَالِكِ، بْنِ أَنَسٍ بِهَذَا الإِسْنَادِ وَزَادَ " لاَ تَبْتَعْهُ وَإِنْ أَعْطَاكَهُ بِدِرْهَمٍ " .
Grade: Sahih 
  
                                        
                
 
                    
                    