Rabbi Hiyya bar Ami said in the name of Ula: "On that same day they decreed, 'If one was traveling when it got dark [and Shabbat began], one must turn over his purse to his non-Jewish companion.'"
The Sages inherited a system of Shabbat observance that proscribed carrying any item of significance from one domain to another. Money is obviously of great material significance in our lives, and we are to leave it safely at home as we travel on Shabbat. But what if, through no fault of our own, we are still on the road with money in our pockets when Shabbat begins. We have seen the solution before: Mishnah Shabbat 24:1 allows us to place the money with a non-Jewish companion for the duration of the sabbath. In our source above, Ula gives us more information about the origins of this solution.
There is a day, renowned in Rabbinic literature, when the students of Shammai, outnumbering those of Hillel, managed to pass eighteen stringent decrees. Among them was the solution of Mishnah Shabbat 24:1, "If one was traveling when it got dark [and Shabbat began], one must turn over his purse to his non-Jewish companion." But how is this stringent? Is this not a leniency? The answer must be that Bet Hillel had an even more lenient solution to the problem. Indeed, the Talmud records that Bet Hillel's suggestion was that the Jewish traveler himself walk with the money, but using a deeply halting gait, less than four steps at a time, to make the act something less than the normal act of carrying. Bet Hillel attempts to preserve the sanctity of Shabbat, while also preserving the self-reliance of the individual Jew under difficult circumstances.