question #3 Sahih Muslim 1014a, Book 12, Hadith 79 : What is the metaphor used to describe the growth of charity given sincerely in Islam?

If anyone gives as Sadaqa the equivalent of a date from that (earning) earned honestly, for Allah accepts that which is lawful, the Lord would accept it with His Right Hand, and even if it is a date, it would foster in the Hand of the lord, as one of you fosters his colt, till it becomes bigger than a mountain.