(a) Abdullah bin Amr (may Allah be pleased with them both) narrated that the Messenger of Allah (peace and blessings be upon him) said: "Sadaqah is not lawful for a rich person, nor for one who is strong and healthy" (that is, one who is fit and has the strength to earn).
(b) In (the narration of) Abu Dawud al-Tayalisi the words are: "nor for one who is strong and powerful."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13155