Sayyiduna Zayd bin Harithah (may Allah be pleased with him) gave a horse in the path of Allah (for jihad); later he saw it being sold in the market, tied up with a rope and emaciated. He bargained over it, then came to the Prophet (peace and blessings be upon him) and said: I had given a horse in the path of Allah, and now I have seen it being sold in the market for a small price, emaciated and tied up with a rope, and I recognise it. Shall I buy it? The Messenger of Allah (peace and blessings be upon him) forbade him from buying the horse.
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4652