Tzedoko 2
When someone comes to collect money for Tzedoko, there is a Mitzvas Lo Saasei min HaTorah of Lo Se'ametz es Levovocho, not to hold back and stiffen one's heart from giving a person Tzedoko.
There is also the Possuk Al Yoshuv Dach Nichlam, not to let a person go empty-handed and humiliated. Lo Se'ametz es Levovcho does not apply if one already gave their requisite amount of Tzedoko that they are supposed to give for that year.
Regarding a person who is collecting from door to door, all one has to give that person is a small amount. One does not really have to give them everything that they need, dei Machsoiro, because they are collecting from other people as well. However, the Mitzvas Lo Saasei of Al Yoshuv Dach Nichlam, not to let a person go empty-handed, is a separate Halocho that applies also when one has already given the requisite amount Tzedoko that year, but it does not apply to someone who is collecting for other people or for institutions, as in these particular cases, one is not letting the collector personally go empty-handed and humiliated, but only the third-party, which is not a problem in this case.
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