הלכה אויף דברים 14:28

According to this system, they should tithe, in a seven year cycle, the first, second, fourth, and fifth years, but on the third and the sixth years of the seven year cycle, after one has tithed ma'asér rishon, one should take out from the remainder another tithe [one-tenth] and give it to the poor. This is called ma'esar ani. In these two years there is no ma'asér sheni but instead ma'esar ani.¹¹⁸See Babylonian Talmud Rosh Hashanah 12b. About this it is written, (Deut. 14:28-29) Every third year you shall bring out the full tithe of your yield of that year, but leave it within your settlements. Then the Levite, [who has no hereditary portion as you have, and the stranger, the fatherless, and the widow in your settlements shall come and eat their fill, so that the LORD your God may bless you in all the enterprises you undertake.] And about this it is written, (Deut. 26:12) When you have set aside in full the tenth part [of your yield in the third year--the year of the tithe--and have given it to the Levite, the stranger, the fatherless, and the widow, that they may eat their fill in your settlements].

If ma'esar ani is divided from the store-chamber, the owners have no right to decide how it is to be apportioned among the poor. Only the poor may come and take regardless of the owner's feelings on the matter. And even if [the owner] is [also] a poor person of Israel, they take it [the tithe] from his possession [for distribution]. But if they divide it up in [his] home [instead of at the store-chamber], then the owner has the right to give it to the poor person that he wants.¹²³See Babylonian Talmud Nedarim 84b and Chullin 131a.

One may not use ma'esar ani to repay a loan, and one may not pay back a favor from it [ma'esar ani], but they may pay out of it something for an act of loving kindness so long as he informs him that it comes from ma'esar ani. But they may not use it to redeem captives [by paying their ransom from ma'esar ani], or buy wedding gifts, or give tzedakah, but they may give it to a town scholar for his benefit.¹²⁹See Tosefta Péah 4:16. They may not, however, take it from the Land of Israel to outside the Land of Israel, as it is said, (Deut. 14:28) But leave it within your settlements, and it is said, (Deut. 26:12) That they may eat their fill in your settlements [teaching that it must be used within the Land of Israel].