Musar su Geremia 50:42

Cruelty is the opposite of Mercy as it is written: "They are cruel and have no compassion" (Jer. 50:42). And this trait of cruelty is not found in righteous people but in the souls of the wicked as it is written: "The tender mercies of the wicked are cruel" (Prov. 12:10). This quality is also found in the impudent as it is written: "An impudent nation that shall have no regard for the person of the old and show no mercy to the young" (Deut. 28:50). And you already know the evil of the trait of impudence. Go forth and learn the evil nature and the punishment of cruelty, for in the matter of the reward of a wicked man — rebellious and disobedient — it is said: "A rebellious man seeks only evil, therefore, a cruel messenger shall be sent against him" (Prov. 12:11). Every cruel person has no quality of kindness in his make up, even towards himself, as it is written: "The merciful man does kindness to his own soul, but he that is cruel troubles his own flesh" (Ibid. 11:17).

One who shuts his eyes from an opportunity to give charity, it is as though he served idols (Kethuboth 68a). Such a man is called "worthless," "wicked," "merciless," and a "sinner." Worthless, as it is said, "Beware that there be not a base thought in thy heart, saying : 'The seventh year, the year of release, is at hand;' and thine eye be evil against thy needy brother, and thou give him nought" (Deut. 15:9). Merciless as it is written, "But the tender mercies of the wicked are cruel" (Prov. 12:10). And he denies his lineage; he is not of the seed of Abraham, Isaac and Jacob, for they were merciful, but he is of the seed of the heathens who are cruel, as it is said, "They are cruel and have no compassion" (Jer. 50:42). And everyone who shows mercy, Heaven has mercy upon him (Shabbath 151b). As it is said, "… and show thee mercy, and have compassion upon thee, and multiply thee" (Deut. 13:18).