Halakha Ulangan 15:8: Mishneh Torah, Gifts to the Poor, Kitzur Shulchan Arukh, Sefer HaChinukh & Sefer HaMitzvot

It is a positive mitzvah to give tzedakah to the poor according to what is fitting for the poor person if he has the means to do so, as it is said, (Deut. 15:8) Rather, you must open your hand and lend him sufficient for whatever he needs. And it is said, (Lev. 25:35) [If your kinsman, being in straits, comes under your authority,] and you hold him as though a resident alien, [let him live by your side:] And it is said (Lev. 25:36), [Do not exact from him advance or accrued interest, but fear your God.] Let him live by your side as your kinsman.¹³⁰See Babylonian Talmud Ketubot 67b-68a.

One is commanded to give to a poor person according to what he lacks. If he has no clothes, they clothe him. If he has no utensils for a house, they buy [them] for him. If he does not have a wife, they arrange a marriage for him. If [the poor person] is a woman, they arrange a husband for marriage for her. Even if it was the custom of [a person who was rich but is now] a poor person to ride on a horse with a servant running in front of him, and this is a person who fell from his station, they buy him a horse to ride upon and a servant to run in front of him, as it is said, (Deut. 15:8) Sufficient for whatever he needs. You are commanded to fill whatever he lacks, but you are not commanded to make him wealthy.¹³¹See Babylonian Talmud Ketubot 67b.

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.