"many days": "days" — two; "many" — three. We are hereby taught that peace is offered for two days, and a third day for the battle. And even though there is no proof for this, there is an intimation of it in (I Samuel 30:1) "And David and his men came to Tziklag on the third day." Variantly: From here it is derived that gentile cities are not besieged fewer than three days before the Sabbath, (so that the siege not extend into the Sabbath); but if the siege began, it is not interrupted. And a sea voyage is not begun fewer than three days before the Sabbath. When is this so? For a long voyage, but for a short one, it is permissible.
"You shall not cut down its tree by wielding an axe against it": This tells me only of iron (i.e., an axe blade). Whence do I derive (the same for destroying it by) diverting a water course from it? From "You shall not destroy its tree" — in any manner.
Variantly: "for from it shall you eat": a tree providing life for a man. R. Yishmael reasoned hence: If the L-rd is so solicitous of the fruits of a tree, how much more so of the tree itself! And if Scripture exhorts against (cutting down) a tree, which only produces fruit, how much more so (does it exhort against destroying) fruit itself!
(דברים כ יט) כִּי תָצוּר אֶל עִיר, בְּמִלְחֶמֶת הָרְשׁוּת הַכָּתוּב מְדַבֵּר.
(Devarim 20:19) "If you besiege a city many days": Scripture here speaks of an optional war.
אֶל עִיר – וְלֹא לִכְרָךְ;
"a city": and not a metropolis;
אֶל עִיר – וְלֹא לִכְפָר.
"a city": and not a village.
יָמִים רַבִּים, יָמִים – שְׁנַיִם, רַבִּים – שְׁלֹשָׁה. מִכָּן אָמְרוּ: אֵין צָרִים עַל עִיר שֶׁל גּוֹיִם פָּחוֹת מִשְּׁלֹשָׁה יָמִים קֹדֶם לַשַּׁבָּת.
"many days": "days" — two; "many" — three. We are hereby taught that peace is offered for two days, and a third day for the battle. And even though there is no proof for this, there is an intimation of it in (I Samuel 30:1) "And David and his men came to Tziklag on the third day." Variantly: From here it is derived that gentile cities are not besieged fewer than three days before the Sabbath, (so that the siege not extend into the Sabbath); but if the siege began, it is not interrupted. And a sea voyage is not begun fewer than three days before the Sabbath. When is this so? For a long voyage, but for a short one, it is permissible.
לְהִלָּחֵם עָלֶיהָ לְתָפְשָׂהּ – וְלֹא לִשְׁבּוֹתָהּ.
"to war upon it, to capture it": and not to destroy it.
לֹא תַשְׁחִית אֶת עֵצָהּ לִנְדֹּחַ עָלָיו גַּרְזֶן, אֵין לִי אֶלָּא גַּרְזֶן. מִנַּיִן אַף לִמְשֹׁךְ הֵימֶנָּה אַמַּת הַמַּיִם? תַּלְמוּד לוֹמַר: לֹא תַשְׁחִית אֶת עֵצָהּ, בְּכָל דָּבָר.
"You shall not cut down its tree by wielding an axe against it": This tells me only of iron (i.e., an axe blade). Whence do I derive (the same for destroying it by) diverting a water course from it? From "You shall not destroy its tree" — in any manner.
דָּבָר אַחֵר: כִּי תָצוּר אֶל עִיר, מַגִּיד שֶׁתּוֹבֵעַ שָׁלוֹם שְׁנַיִם שְׁלֹשָׁה יָמִים, עַד שֶׁלֹּא נִלְחָם בָּהּ. וְכֵן הוּא אוֹמֵר (שמואל ב א א): ״וַיֵּשֶׁב דָּוִד בְּצִקְלַג יָמִים שְׁנַיִם״. וְאֵין צָרִים עַל עִיר בַּתְּחִלָּה בְּשַׁבָּת, אֶלָּא קוֹדֶם לַשַּׁבָּת שְׁלֹשָׁה יָמִים. וְאִם הִקִּיפוּהָ וְאֵרְעָה שַׁבָּת לִהְיוֹת – אֵין הַשַּׁבָּת מַפְסֶקֶת מִלְחַמְתָּהּ. זֶה אֶחָד מִשְּׁלֹשָׁה דְבָרִים שֶׁדָּרַשׁ שַׁמַּי הַזָּקֵן: אֵין מַפְלִיגִים אֶת הַסְּפִינָה לַיָּם הַגָּדוֹל אֶלָּא קוֹדֶם לַשַּׁבָּת שְׁלֹשָׁה יָמִים. בַּמֶּה דְּבָרִים אֲמוּרִים? בְּדֶרֶךְ רְחוֹקָה, אֲבָל בְּדֶרֶךְ קְרוֹבָה מַפְלִיגִים אוֹתָהּ.
כִּי מִמֶּנּוּ תֹאכֵל – מִצְוַת עֲשֵׂה; וְאֹתוֹ לֹא תִכְרֹת – מִצְוַת לֹא תַעֲשֶׂה.
"For from it you shall eat": a positive commandment;
כִּי הָאָדָם עֵץ הַשָּׂדֶה, מְלַמֵּד שֶׁחַיָּיו שֶׁל אָדָם אֵינָם אֶלָּא מִן הָאִילָן. רַבִּי יִשְׁמָעֵאל אוֹמֵר: מִכָּן חָס הַמָּקוֹם עַל פֵּרוֹת הָאִילָן קַל וָחוֹמֶר מֵאִילָן, וּמָה אִילָן שֶׁעוֹשֶׂה פֵּרוֹת – הִזְהִירְךָ הַכָּתוּב עָלָיו, פֵּרוֹת עַצְמָם – עַל אַחַת כַּמָּה וְכַמָּה!
"but it you shall not cut down": a negative commandment.
לָבוֹא מִפָּנֶיךָ בַּמָּצוֹר, הָא אִם מְעַכֶּבְךָ לָבוֹא מִפָּנֶיךָ בַּמָּצוֹר – קָצְצֵהוּ!
Variantly: "for from it shall you eat": a tree providing life for a man. R. Yishmael reasoned hence: If the L-rd is so solicitous of the fruits of a tree, how much more so of the tree itself! And if Scripture exhorts against (cutting down) a tree, which only produces fruit, how much more so (does it exhort against destroying) fruit itself!