Halakha Ulangan 15:7: Mishneh Torah, Human Dispositions, Mishneh Torah, Gifts to the Poor, Mishneh Torah, Negative Mitzvot & Shulchan Arukh, Yoreh De'ah

The straight path is the mean disposition found in each and every tendency of all the human tendencies. Such tendency is removed from both extremes an equal distance, and is not nearer to one than to the other. Therefore have the wise men of yore commanded that man should ever review his tendencies,¹Sotah, 5b. C. estimate them, and direct them toward the middle-path so that he will be sound in body. How may one do it? He should not be an excitable person, easily angered; nor like the dead without feelings, but adopt a middle-course, not to become indignant, save only at something big which is worthy enough to be angry at, so that the like should not be done another time. Likewise shall he not crave for aught save the things which the body requires, and without which it is impossible to be, as the subject is spoken of: "The righteous eateth to the satisfying of his soul" (Pro. 13.25). Likewise shall he not continue to fatigue himself in his affairs, save to acquire what is necessary for him to live on for the time being as the subject is mentioned, saying: "A little that a righteous man hath is better" (Ps. 37.16). He should not be too close-fisted, nor yet squander his money, but give Z'dakah within the means of his hand, and lend accordingly to the needy. He should not be too optimistic and playful, nor too pessimistic and mournful, but spend all of his days in good cheer and with a pleasant countenance. So should he measure all the rest of his tendencies. And this path is the path of the wise men. Every man whose tendencies are mean tendencies of the middle-course, is called wise.

Anyone who sees a poor person begging and averts his eyes from him and does not give him tzedakah transgresses a negative mitzvah, as it is said, (Deut. 15:7) [If, however, there is a needy person among you, one of your kinsmen in any of your settlements in the land that the LORD your God is giving you,] do not harden your heart and shut your hand against your needy kinsman.

The redemption of captives held for ransom takes precedence over sustaining the poor and clothing them. You do not find a mitzvah greater than the redemption of captives, for captivity is in the same category as famine, drought, or exposure, and one stands in danger to one's life. One who averts his eyes from redeeming [the captive] transgresses [the commandment], (Deut. 15:7) Do not harden your heart and shut your hand, and (Lev. 19:16) Do not stand upon the blood of your neighbor, and (Lev. 25:53) He shall not rule ruthlessly over him in your sight, and nullifies the commandment (Deut. 15:8) You must open your hand, and the commandment, (Lev. 25:36) Let him live by your side as your kinsman, and (Lev. 19:18) Love your fellow as yourself, and (Proverbs 24:11) If you refrained from rescuing those taken off to death, [those condemned to slaughter--if you say, "We knew nothing of it," surely He who fathoms hearts will discern], and many such sayings. You cannot find a greater mitzvah than the redemption of captives.¹⁵³See Babylonian Talmud Bava Batra 8a-b on the importance of redeeming captives and Chullin 7a where Rabbi Phineas ben Yair travels to redeem captives and, on the way, a river parts for him, enabling him to pass through on dry land to fulfill his duty.