The Messenger of Allah ﷺ said, "Whoever gives in charity the equivalent of a date from lawful earnings, and Allah accepts only what is good, Allah receives it in His right hand and then nurtures it for the giver just as one of you raises his foal, until it becomes as great as a mountain."
قال رسول الله ﷺ من تصدق بعدل تمرة من كسب طيب- ولا يقبل الله إلا الطيب- وإن الله يتقبلها بيمينه، ثم يربيها لصاحبه كما يربي أحدكم فلوه حتى تكون مثل الجبل.
Bukhari related it in the Book of Zakat (1410), and Muslim in the Book of Zakat (64:1014), both from the hadith of Abu Salih, from Abu Hurairah, as mentioned. Their wording is the same, and Muslim added, "or his young she-camel."His saying "al-filw" with the lam either silent or with a damma, means the young foal. It is called this because it is "weaned" (fuliya) from its mother, that is, separated and set apart.His saying "al-qalus" means a young she-camel, and the term is not applied to the male.