On Purim we are obligated to give "Matanoth LaEbyonim", gifts to at least two poor people. What if two poor people approach you, and you only have a large bill in your pocket? Can you give the bill to one of them saying, "I want you to split this in two. You keep half and your friend keeps half". If you do so, have you fulfilled the Miswah of Mattanoth LaEbyonim (giving charity to two people)?
The answer in Torah Lishmah is, as it tells us in the Gemara of Pesahim, "Ein 'Osim Miswoth Habiloth", (you cannot do Miswoth in packages), but rather, they have to be done individually.
So even if two poor people come up to you and both stretch their hands out, hoping to receive something, giving it in one package as it were to one person, does not work. But rather, you have to go and change the money, and give to each of them individually.
(See Torah Lishmah, Orah Hayyim, Oth Qof Sad)
