(יט) כִּֽי־תָצ֣וּר אֶל־עִיר֩ יָמִ֨ים רַבִּ֜ים לְֽהִלָּחֵ֧ם עָלֶ֣יהָ לְתָפְשָׂ֗הּ לֹֽא־תַשְׁחִ֤ית אֶת־עֵצָהּ֙ לִנְדֹּ֤חַ עָלָיו֙ גַּרְזֶ֔ן כִּ֚י מִמֶּ֣נּוּ תֹאכֵ֔ל וְאֹת֖וֹ לֹ֣א תִכְרֹ֑ת כִּ֤י הָֽאָדָם֙ עֵ֣ץ הַשָּׂדֶ֔ה לָבֹ֥א מִפָּנֶ֖יךָ בַּמָּצֽוֹר׃ (כ) רַ֞ק עֵ֣ץ אֲשֶׁר־תֵּדַ֗ע כִּֽי־לֹא־עֵ֤ץ מַאֲכָל֙ ה֔וּא אֹת֥וֹ תַשְׁחִ֖ית וְכָרָ֑תָּ וּבָנִ֣יתָ מָצ֗וֹר עַל־הָעִיר֙ אֲשֶׁר־הִ֨וא עֹשָׂ֧ה עִמְּךָ֛ מִלְחָמָ֖ה עַ֥ד רִדְתָּֽהּ׃ (פ)
(19) When in your war against a city you have to besiege it a long time in order to capture it, you must not destroy its trees, wielding the ax against them. You may eat of them, but you must not cut them down. Are trees of the field human to withdraw before you into the besieged city? (20) Only trees that you know do not yield food may be destroyed; you may cut them down for constructing siegeworks against the city that is waging war on you, until it has been reduced.
(י) כי האדם עץ השדה. שחייו של אדם (אינו אלא) מן האילן.
Because a human is a tree of the field. Humanity can only exist because of trees.
(יט) כי האדם עץ השדה. הרי כי משמש בלשון דלמא שמא האדם עץ השדה להכנס בתוך המצור מפניך להתיסר ביסורי רעב וצמא כאנשי העיר, למה תשחיתנו:
(19) Are trees of the field human? "
Is the tree of the field human such that they can retreat from the suffering of famine and thirst like the inhabitants of the city?
...אמר רב זוטרא האי מאן דמיכסי שרגא דמשחא ומגלי נפטא קעבר משום בל תשחית...
One who covers an oil lamp [causing the flame to burn inefficiently] or uncovers a kerosene lamp [allowing the fuel to evaporate faster] violates the prohibition of bal tashchit.
אמר רב חייא בר אבין אמר שמואל הקיז דם ונצטנן עושין לו מדורה אפי' בתקופת תמוז שמואל צלחו ליה תכתקא דשאגא רב יהודה צלחו ליה פתורא דיונה לרבה צלחו ליה שרשיפא וא"ל אביי לרבה והא קעבר מר משום (דברים כ, יט) בל תשחית א"ל בל תשחית דגופאי עדיף לי
Rav Hiyya bar Avin said in the name of Shmuel, “When someone gets chills [on Shabbat] after bloodletting, we may make a fire [for warmth or cooking]...” For Samuel himself, they chopped up an expensive, drumshaped stool made of shagawood. For Rav Judah, they chopped up a table made of yavnahwood. For Rabbah they chopped up a [wooden] chair. At which point Abbaye said to Rabbah, "Aren’t you breaking the rule against bal tashchit?” He
replied, “Avoiding the ‘bal tashchit’ of my body takes priority for me.”
Just as one has to be careful with their body not to break or hurt anything... so to does one have to be careful in everything else to make sure that they don’t break or hurt anything. And anytime that someone breaks a vessel or rips a garment or destroys a house or covers over a well or destroys food or drink or anything else that a human can benefit from has broken a negative commandment as it says, “do not destroy a tree...”
One must be careful not to destroy, waste, or damage one’s money...
"Do not destroy anything" is the first and most general call of God... If you should now raise your hand to play a childish game, to indulge in senseless rage, wishing to destroy that which you should only use... if you should regard the beings beneath you as objects without rights... instead of using them only as the means of wise human activity -- then God's call proclaims to you, "Do not destroy anything! Be a mench!