סימן פט סעיף א
כְּלִי שֶׁלּוֹ שֶׁהִנִּיחַ עָלָיו בְּעֶרֶב שַׁבָּת דָּבָר מֻקְצֶה בְּכַוָּנָה, וְהָיְתָה דַּעְתּוֹ שֶׁיְהֵא מֻנָּח שָׁם בְּהַכְנָסַת שַׁבָּת, נַעֲשָׂה הַכְּלִי בָּסִיס לְדָבָר הָאָסוּר. וַאֲפִלּוּ נִטַּל מִשָּׁם הַמֻּקְצֶה בְּיוֹם הַשַׁבָּת, מִכָּל מָקוֹם כֵּיוָן שֶׁהָיָה מֻנָח שָׁם בֵּין הַשְׁמָשׁוֹת וְנַעֲשָׂה אָז הַכְּלִי בָּסִיס לַדָבָר הָאָסוּר, אָסוּר לְטַלְטְלוֹ גַּם אַחַר כָּךְ כָּל הַיּוֹם, אֲפִלּוּ לְצֹרֶךְ גּוּפוֹ וּלְצֹרֶךְ מְקוֹמוֹ.
If you intentionally placed a muktzeh object upon your vessel on Friday1According to some, this applies even where it is מְלַאכְתּוֹ לְאִיסוּד —i.e. muktzeh due to it being an object that is used for work prohibited on Shabbos. (This is the most lenient type of muktzeh since you may move it when you need it for a permitted use or for the space it occupies.) [Tehillah LeDavid 308: 1] Yeshuos Yaakov is inclined to permit בָּסִיס for מְלַאכתּוֹ לְאִיסוּר Peri Megadim (308) remains doubtful. and you intended that it be there2Or if it is the usual place for the muktzeh to be kept. [Mishnah Berurah 309: 18] Accordingly, money that was left in a purse would render the purse a בָּסִיס. However, Biur Halachah (266: 12) cites Derech Chaim that the purse is not a בָּסִיס . A possible explanation might be that he is referring to a purse which is normally emptied before Shabbos. [See Chazon Ish 49: 10; also Mishnah Berurah 310: 25.] at the onset of Shabbos,3See paragraph 5. This applies only if you intended it to remain there the entire twilight period. [Rabbi Akiva Eiger 310; Peri Megadim 279; Shulchan Aruch Harav 310: 7; Mishnah Berurah 309: 19] the vessel is considered a base for a prohibited object [muktzeh]. Even if the muktzeh object was removed on Shabbos; nevertheless, since it lay there at twilight, and the vessel then became a base for a prohibited object, it is forbidden to be handled afterwards for the rest of the Shabbos day4Something that was muktzeh at twilight remains muktzeh the rest of Shabbos, even if the cause of the muktzeh was removed. even if you need the object itself or the space it occupies.5A בָּסִיס attains the same degree of muktzeh as the muktzeh object which created the בָּסִיס.
תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)