전도서 7:9의 Musar

The sage has forbidden it, saying (Eccl. vii. 9), "Be not hasty in thy spirit to be angry." Furthermore the verse makes clear the reason for his forbidding it in the expression (ib.) "For anger resteth in the bosom of fools." The wrathful deserves to be called "fool." It is impossible in most cases for the man of violent wrath to be secure from grave sin and serious transgression. Thus the sage spake (Prov. xxix. 22): "A wrathful man aboundeth in transgression." Thou wilt notice that most men, when they become wroth and violently angry, take no heed of the disaster which they may incur through the violence of their anger, like him of whom it is said (id., 11), "A fool uttereth all his mind," and on the other hand (ib.). "But a wise man keepeth it till afterward." Therefore our masters, peace be upon them, sought to interdict the immoderate exercise of this quality, saying, "He who rends his garments in wrath is like unto an idolater." According to this, a superior man must not be violent in wrath, for he accustoms himself to the qualities of the wild and wicked beast. Nor must he be so gentle as never to become wrathful, for this were characteristic of little boys.¹Attributed to Aristotle in an article on "Ruhmliche Denkmale der Joiner aus den Tiirkischen," Diez (vol. i., p. 83); cf. Hatch (above cited, p. 223). The discreet stand with reference to this is to take the intermediate course. Thou must know that man's reason is perfected when it subdues his wrath. Thus Scripture says (Prov. xix. 11), "The discretion of a man deferreth his anger." Ptolemy, the sage, said of wrath, "When thou becomest wrathful, pardon, for if thou dost not yield, the taking²Versified by Steinschneider ("Manna," chap, i., p. 89); cf. Bahya, vi. 7, and Brull (p. 77, note 3). of vengeance is a sign of weakness."

Our sages of blessed memory warned us to not get angry even for the sake of a mitzva (see Shab.34a, 105b), not even a teacher with his student or a father with his son. This is not to say he should not chastise them, rather he should surely chastise them, just not out of anger, but rather, with no other purpose than guiding them along the right path. Any anger that he shows to them should be only of the face not anger of the heart. Shlomo said: "Be not quick in your spirit to be angry [for anger rests in the heart of fools]" (Kohelet 7:9) and it is written "For anger slays the fool" (Iyov 5:2), and our sages of blessed memory said: "in three ways a man is recognized: through his cup, through his wallet and through his anger" (Eruvin 65b).

Our Sages said further : "He who loses his temper, even the Divine Presence, is unimportant in His eyes (Nedarim 22b), as it is written "The wicked in the pride of his countenance (saith) 'He will not require', All his thoughts are 'There is no God' " (Ps. 10:4). And it (anger) also causes him to forget his studies of Torah and increases his folly as it is said : "For anger resteth in the bosom of fools" (Eccl. 7:9) and "A fool will not understand" (Ps. 92:7), and, "But a fool unfoldeth folly" (Prov. 13:16). You may be sure that his sins are more plentiful than his merits, as it is said : "An angry man stirreth up strife" (Ibid. 29:22) and his punishment is very great as it is said : "A man of great wrath shall suffer punishment" (Ibid. 19:19).