וְלֹ֤א יִשְׁכְּבוּ֙ אֶת־גִּבּוֹרִ֔ים נֹפְלִ֖ים מֵעֲרֵלִ֑ים אֲשֶׁ֣ר יָרְדֽוּ־שְׁא֣וֹל בִּכְלֵֽי־מִלְחַמְתָּם֩ וַיִּתְּנ֨וּ אֶת־חַרְבוֹתָ֜ם תַּ֣חַת רָאשֵׁיהֶ֗ם וַתְּהִ֤י עֲוֺֽנֹתָם֙ עַל־עַצְמוֹתָ֔ם כִּֽי־חִתִּ֥ית גִּבּוֹרִ֖ים בְּאֶ֥רֶץ חַיִּֽים׃
И те, кто уступают необрезанным, не будут лежать с могущественными, которые пали в мир преисподней со своим оружием войны, мечи которого лежат под их головами, а чьи беззакония - на их костях; потому что ужас могущественных был на земле живых.
Mishneh Torah, Fasts
The night of the Ninth of Av is like the day in every matter. And we may only eat from when it is still day (on the previous day). And its twilight [time] is forbidden like on Yom Kippur. And one should not eat meat or drink wine on the meal that pauses [our eating before the fast]. But he may drink wine from the winepress that is three days old or less. And he may eat salted meat that is three days old or more. And he should not eat eat two [cooked] dishes.
Shulchan Arukh, Orach Chayim
All that eat and drink on Tisha B'av, will not see the joy of Jerusalem. And all that mourn on Jerusalem, will merit and see it in her joy. And that eat meat and drink wine at the Parting Meal, on him the verse says their iniquities are on their bones (Ezekiel 32:27).