סימן קכד סעיף טו
בְּעִנְיַן מְלָאכָה, אָנוּ נוֹהֲגִים שֶׁכָּל מְלָאכָה שֶׁיֵּשׁ בָּהּ שִׁהוּי קְצָת, אֲפִלּוּ אֵינָהּ מַעֲשֵׂה אֻמָּן אֶלָּא מַעֲשֵׂה הֶדְיוֹט, אֲסוּרִין בַּלַּיְלָה וּבַיּוֹם עַד הַצָהֳרָיִם. אֲבָל דָּבָר שֶׁאֵין בּוֹ שִׁהוּי, כְּגוֹן הַדְלָקַת נֵרוֹת וּקְשִׁירָה וְכַיּוֹצֵא בוֹ, מֻתָּר. וּלְאַחַר הַצָהֳרַיִם עוֹשִׂים כָּל הַמְּלָאכוֹת. וְכֵן מַשָּׂא וּמַתָּן נוֹהֲגִים לֶאֱסוֹר קֹדֶם הַצָהֳרַיִם, וּלְאַחַר הַצָהֳרַיִם מַתִּירִים. אֲבָל מִי שֶׁהוּא יְרֵא שָׁמַיִם, יֵשׁ לוֹ לְהַחְמִיר כָּל הַיּוֹם, בֵּין בִּמְלָאכָה, בֵּין בְּמַשָּׂא וּמַתָּן, שֶׁלֹּא יַסִּיחַ דַּעְתּוֹ מִן הָאֲבֵלּוּת. וְעַל יְדֵי אֵינוֹ יְהוּדִי, מֻתָּר לַעֲשׂוֹת כָּל מְלָאכָה. דָּבָר הָאָבֵד, מֻתָּר לַעֲשׂוֹת גַּם בְּעַצְמוֹ. לַחֲלֹב הַפָּרוֹת, טוֹב לַעֲשׂוֹת עַל יְדֵי אֵינוֹ יְהוּדִי. וְאִם אִי אֶפְשָׁר, מֻתָּר בְּעַצְמוֹ (תקנד).
It is our custom, that any work requiring time, even work for which no skill is required, is forbidden the night (of Tishah beAv), and in the daytime, until noon. But work that does not take long to do, like lighting candles or tying a knot, is permitted.24Regarding writing, Eliyahu Rabbah, in the name of Knesseth Hagedolah, says that you may be lenient; and Mateh Yehudah says that writing on Tishah beAv is governed by the same rules as on Chol haMoed. (see Biyur Halachah 554:22) In the afternoon, all work is permitted. It is also the custom to forbid doing business before noon, but to permit in the afternoon.25However, it is best not to get involved in your business, to the extent that you will forget that it is a day of mourning. This also applies to working. (Mishnah Berurah 554:49) However, a God-fearing man should be stringent in his observance the entire day, and not do any work, nor do any business, so that his mind should not be distracted from mourning.26Shulchan Aruch 554:24 rules that one who does work on Tishah beAv will not see any blessing from that work. Mishnah Berurah explains that he will not see blessing from the profit made from working on Tishah beAv. See note 25, that this refers only in a situation where he completely forgot that it is a day of mourning. It is permitted, however, to instruct a non-Jew to do any kind of work for you.27This does not include building or exterior work that is in the public view which is forbidden. (Ibid. 554:46) Any work, that if not done, would entail a loss, you are permitted to do yourself. Milking the cows preferably should be done by a non-Jew, but when that is impossible, you are permitted to do it yourself.
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.)