Mishkat al-Masabih — Hadith #49140

On the authority of Omar Ibn Al-Khattab, may God be pleased with him, he said: I got a horse for the sake of God, but the one who had it lost it, so I wanted to buy it. I thought he was selling it cheaply, so I asked the Prophet, may God bless him and grant him peace, and he said: “Do not buy it and do not return your charity, even if he gives it to you.” With a dirham, the one who returns in his charity is like a dog who returns in his vomit.” And in a narration: “Do not neglect your charity, for the one who is negligent in his charity is like the one who is negligent in his vomit.”