“If there shall be a destitute person among you, any of your brethren in any of your cities, in your land that Hashem, your G-d, gives you, you shall not harden your heart or close your hand against your destitute brother. Rather, you shall open your hand to him; you shall lend him his requirement, whatever is lacking to him.” (Devarim 15:7-8)
“You shall surely give him, and let your heart not feel bad when you give him, for in return for this matter, Hashem, your G-d, will bless you in all your deeds and in your every undertaking.” (Devarim 15:10)
These verses are the Torah source for the obligation to give tzedaka(charity) when a poor person requests it. The Rambam writes (Hilchot Matanot Aniyim 10:1) that we must be more careful about the mitzvah of tzedaka than all other positive mitzvoth, since tzedaka indicates one is a Tzaddik and a descendant of Avraham Avinu, as the passuk says, “For I love him since he commands his children…to do tzedaka.” (Bereshit 18:19)
In his introduction to Yoreh Deah the Chatam Sofer writes that Chanoch walked with G-d and was like an angel, but nevertheless Hashem chose Avraham Avinu because He can create as many angels as He wishes, but He wanted people to do chessed and tzedaka. Even though Avraham Avinu did not reach the exalted prophetic levels of Chanoch, Chanoch had to remain isolated to achieve that, and his generation was wiped out in the flood, while Avraham Avinu in fact saved his generation due to his righteousness and acts of chessed and tzedaka.
One of the main purposes of creation is for man to become like his Creator, in line with the mitzvah of “going in His ways”. Just as Hashem is merciful we are required to act with mercy. In this world there is no better way of connecting to Hashem than to be like Him, to be concerned for others and to help them.
Since tzedaka is a positive mitzvah, why are we not required to make a brachah when we give? The Rashba answers (in Teshuva18) that the fulfillment of the mitzvah is not totally dependent on the giver, since perhaps the recipient will refuse to accept the charity, and therefore one cannot make a brachah.
One of the important aspects of the mitzvah of tzedaka which unfortunately tends to be neglected is the requirement to give tzedaka with a smile. This halacha is brought in the Rambam (Hilchot Matanot Aniyim 10:4-5) and is also paskened in the Shulchan Aruch (Yoreh Deah 249:3). In brief, one who gives tzedaka with a sour face, even if he gives thousands, he gains nothing from his mitzvah. In fact, he must give tzedaka with a smile, happily, and also share in the suffering of the recipient. In fact, someone who gives tzedaka in such a manner is doing an aveira, as the Shach writes (Yoreh Deah 249:5) – it is a transgression of that learnt from the verse, “Your heart shall not be bitter when giving him.”
The reason that people tend to find it difficult to give tzedaka with a smile is because there are so many requests for help and the giver feels he’s doing the recipient a favor, when in fact this is not a favor, nor a custom nor a nice idea – it’s a full-blown Torah mitzvah. One should be grateful for the opportunity to do any mitzvah, and certainly this most essential mitzvah. If it’s hard to feel joy or gratitude when giving tzedaka, at the very least one should think to oneself what it would be like to be in the recipient’s situation. It is well-known that financial security can vanish in an instant, whether due to sudden loss of employment, illness, or any other reason, and so everyone should be able to imagine the situation of a person forced to go collecting from door-to-door.
The Rambam writes that nobody will become poor or suffer in any way as a result of giving tzedaka. Therefore one should give tzedaka happily, which is an integral part of the mitzvah, not just an added extra. There is also a halachic ramification to the fact that giving happily is part of the mitzvah – it means that someone who does not have enough money to give tzedaka is still required to comfort the poor by speaking to him kindly and sharing in his suffering. One should feel for the poor man the same as how his father must feel about his son’s suffering.