Sefer Otzar Chaim relates that during his travels, Rav Boruch of Mezhibuzh zy”a once came to the city of Kishiniv. At the time, the city was experiencing a drought and a fast had been declared for that day, with all the residents gathered in the shul and davening for rain.
Rav Boruch told them to stop fasting immediately and, instead, to prepare a festive meal that he and his chasidim would share with them. The Rov and Rosh Hakahal complained to him that they had declared a fast for that day to pray for desperately- needed rain, and they found it inappropriate that he wanted to make a seudah. Rav Boruch responded, “By refraining from food and drink, you are proving to Hashem that you don’t need to eat or drink to live, so why should He send rain? It is better to eat and drink so that Hashem sees that you need rain to grow crops and have enough food, which you really do need.”
He concluded, “The Torah tells us to eat, become satiated and bless Hashem. This means that one can also praise and bless Hashem after he has eaten to satiation.”
