By Rabbi Berach Steinfeld
The Gemara in Succah, daf mem vov, amud bais discusses that Reb Zeira said that a person should be careful not to say to a child, “I will give you something” and then not keep his word; because that would teach the child to lie.
Reb Elchanan Wasserman and the Kehilas Yaakov both ask the following question. Why does the gemara say the reason you should not do this is because you will teach the child to lie? There is a stronger reason. In most instances, a koton is considered poor since he does not sustain himself. We pasken that one who promises something to tzedakah may not regret doing so as it is considered a vow, like nidrei tzedakah.
Reb Elchanan answers this question by saying that the Gemara is dealing with a case concerning a koton who has received a big inheritance, so he would not be considered a poor person. Therefore, the only reason one must keep his promise after saying he will give a child something is due to the fact that one will thereby teach the child to lie.
The Kehilas Yaakov answers the above question by saying that the Gemara is dealing with a case where the father is sustaining the koton so he is not considered poor. This applies both in a case where the koton is under six and the father is required to sustain his child; or even in the case where the child is above six and the father may not be required to sustain him, but nevertheless since it is the norm for a father to supply the needs of his child, the child would not be considered a poor person. There is therefore no requirement to give tzedakah; hence the reason stated by the Gemara that we don’t want to teach the child to lie, so one must therefore keep his promises to the child.
The Sefer Niv Sefasaim explains that the Gemara is dealing with a scenario wherein someone promises a child some candy. The treats promised are not healthful and will not keep him alive and well; it therefore would not fall under the category of tzedakah. It is interesting to note that giving candy to a gadol would be considered tzedakah as the Gemara states that if a person is used to having a horse running before him and he falls on hard times, it is a mitzvah to help him retain his level of luxuries. The difference here is that we are discussing a koton; and there is no obligation to provide him with all his extra desires.
The most important thing we learn here is how important it is to keep our word and fulfill our promises.