Ulla Finds Rabbah bar Rav Huna Measuring Bathwater
Ulla sees Rabbah bar Rav Huna measuring his bathwater on Shabbos and rebukes him; Rabbah answers that he is only measuring idly, with no purpose.
The final mishnah discusses the permissibility of measuring on Shabbos. The Gemara doesn’t elaborate much on that topic, leaving a lot of loose ends. The Gemara provides a brief anecdote to shed some light on the issue. Ulla visited the house of the exilarch, the reish gelusa, and found Rabbah bar Rav Huna bathing on Shabbos. In the times of the Talmud, it was permitted to take a cold bath on Shabbos. Nowadays, we have a custom to refrain from doing so except in cases of moderate discomfort. Ulla noticed that Rabbah was measuring the water. Rabbah found himself to be on the receiving end of Ulla’s rebuke. Ulla challenged, “The mishnah only permits measuring on Shabbos to fulfill a mitzvah need. How can you measure the bathwater on Shabbos? It is not relevant to any mitzvah.” Rabbah replied, “I am just idly measuring the water to no end. I have no need to know the measurement. It is permitted to mindlessly measure on Shabbos.” End of story!