A Greek philosopher came to Rabban Gamliel with a complaint disguised as a question. "Why," he asked, "should I give to the poor with a smile? Giving drains my purse. A smile on top of it — that seems excessive."
Rabban Gamliel answered with the quiet clarity of a merchant who has read the small print. "Because," he said, "when you give to the poor, God Himself is the guarantor of the loan. You are not making a gift. You are making a deposit with the most reliable institution in the universe. And the donor is certain of his reward."
The philosopher paused. Gamliel continued. "Proverbs 19:17 puts it plainly: He that hath pity upon the poor lendeth unto the Lord; and that which he hath given will he pay him again. Every coin you place in the outstretched hand of a hungry person has just become a loan to Heaven. Heaven never defaults. Heaven pays interest no human bank can match."
Rabban Gamliel's closing beat: a man does not wear a sour face when he is closing the most profitable transaction of his life. A smile on the giving hand is simply the honest expression of a man who knows the exchange rate.
Gaster's Exempla (no. 183, 1924) records this story because it reframes the entire economics of tzedakah. The giver is not the loser in the exchange. He is the one who, by any sane accounting, should be laughing as he hands over the money.