(a) In Shabbos, 148a, Rav Yehuda confiscated another sage's cloak. Rav Yehuda did this to compel the sage to come to his lecture. How was Rav Yehuda permitted to take someone's cloak? Isn't it forbidden to steal, even if the intent is to return it?
(b) In Shabbos, 150b, the Gemara says that it is ok on Shabbos to walk to the end of the Techum and wait until Shabbos ends to take care of something beyond the Techum. But isn't this Uvdah d'Chol, since it is against the spirit of Shabbos?
Thanks.
Kol Tuv
Yosef Schwartz
(a) Rav Yehudah was permitted to do such a thing because he was the head of the Beis Din, and Beis Din has the right to expropriate the property of individual's ("Hefker Beis Din Havi Hefker") when they deem it necessary. In this case he deemed it necessary for the honor of the Rosh Yeshiva.
(b) It is only prohibited to walk to the end of the Techum on Shabbos if one's intention is in order to an action after Shabbos which is forbidden to do on Shabbos. If he merely wants to walk further after Shabbos, although it is prohibited to do so on Shabbos, it is permitted to go to the end of the Techum and wait there.
Perhaps it is not "Uvda d'Chol" since the act of *walking* is permitted on Shabbos; only walking *out of the Techum* is prohibited. Since it is never evident where a person's Techum ends (because even if we know where he lives, he may have made an Eruv Techumim), standing by the end of one's Techum in order to proceed immediately after Shabbos cannot be called "Uvda d'Chol."
Be well!
M. Kornfeld