Bal tashchit

Bal tashchit (Hebrew: בל תשחית) ("do not destroy") is a basic ethical principle in Jewish law.

The principle is rooted in the Biblical law of Deuteronomy 20:19–20. “When you lead a siege against a city many days … you may not destroy any tree of hers, to hew an ax against it, for from it you will eat, and you may not cut it off! Is the tree of the field a person, to come before you in the siege? Only a tree that you know is not a tree for food, that one you may destroy and cut off, and build siegeworks…” In the Bible, the command is said in the context of wartime and forbids the cutting down of fruit trees in order to assist in a siege.

In early rabbinic law however, the bal tashchit principle is understood to include other forms of senseless damage or waste. For instance, the Babylonian Talmud applies the principle to prevent the wasting of lamp oil, the tearing of clothing, the chopping up of furniture for firewood, or the killing of animals. In his explanation of this law, the Chinuch (Mitzvah 529) writes that "it is the practice of very righteous people not to waste anything, even a grain of mustard".

The logic behind this principle is that if even in a time of war one could not destroy fruit trees, all the more so should one not destroy or waste anything under normal circumstances. The Talmud even goes so far as to state that "…one who tears his clothes or breaks his vessels or scatters his money in anger should be considered like an idol worshipper (see b.Shabbat 105b; cf. also, b.Shabbat 67b)."

However, even though this moral principle could hardly be given a stronger formulation, in all cases, bal tashchit is invoked only for destruction that is deemed unnecessary. Destruction is explicitly condoned when the cause or need is adequate. For example, the law as codified determined that if one could profit more from cutting down a fruit tree and selling its wood than from leaving it standing and harvesting its fruit, this did not count as wasting (b. Baba Qama 91b–92a, Mishneh Torah Shofetim, Hilkhot Melakhim 6:9).

Modern day applications of this law include an injunction against wasting food.

In contemporary Jewish ethics on Judaism and ecology, advocates often point to bal tashchit as an environmental principle. (Jewish vegetarians also point to bal tashchit as one justification for vegetarianism or veganism, arguing that eating meat and raising animals in general is wasteful. ) Nevertheless, although bal tashchit may be broadly applied to environmental ethics, its limitation in the case where one may profit through a destructive act makes the application of the laws of bal tashchit to environmental issues complicated.

Eilon Schwartz examines these limitations of bal tashchit in his work. Both David Mevorach Seidenberg and Tanhum Yoreh have proposed ways to buttress the law of bal tashchit so that it may play a more meaningful role in the development of Jewish environmental ethics.