The Rambam · Sefer Zeraim
הלכות מתנות עניים ו׳Gifts to the Poor 6
Chapter 6 of 10 in Gifts to the Poor — 17 halachot
Halacha 1א׳
מַתָּנָּה אַחֶרֶת שִׁשִּׁית יֵשׁ לָעֲנִיִּים בְּזֶרַע הָאָרֶץ וְהוּא הַמַּעֲשֵׂר שֶׁנּוֹתְנִין לָעֲנִיִּים וְהוּא הַנִּקְרָא מַעֲשַׂר עָנִי:
Another, sixth type of gift for the poor from agriculture is the tithe that they give to the poor, and it is called ma'esar ani [the "tithe for the poor"].
Halacha 2ב׳
וְזֶהוּ סֵדֶר תְּרוּמוֹת וּמַעַשְׂרוֹת. אַחַר שֶׁקּוֹצֵר זֶרַע הָאָרֶץ אוֹ אוֹסֵף פְּרִי הָעֵץ וְתִגָּמֵר מְלַאכְתּוֹ מַפְרִישׁ מִמֶּנּוּ אֶחָד מִן הַחֲמִשִּׁים. וְזֶהוּ הַנִּקְרָא תְּרוּמָה גְּדוֹלָה וְנוֹתְנָהּ לַכֹּהֵן. וְעַל זֶה נֶאֱמַר בַּתּוֹרָה (דברים יח ד) "רֵאשִׁית דְּגָנְךָ תִּירשְׁךָ וְיִצְהָרֶךָ". וְאַחַר כָּךְ מַפְרִישׁ מִן הַשְּׁאָר אֶחָד מֵעֲשָׂרָה. וְזֶהוּ הַנִּקְרָא מַעֲשֵׂר רִאשׁוֹן. וְנוֹתְנוֹ לַלֵּוִי. וְעַל זֶה נֶאֱמַר בַּתּוֹרָה (במדבר יח כד) "כִּי אֶת מַעְשַׂר בְּנֵי יִשְׂרָאֵל" וְגוֹ' וְנֶאֱמַר (במדבר יח כא) "וְלִבְנֵי לֵוִי הִנֵּה נָתַתִּי אֶת כָּל מַעֲשֵׂר בְּיִשְׂרָאֵל":
And this is the system of gift-offerings and tithes: After one has harvested the seeds of the earth or gathered the fruit of the trees and has completed one's labor, one must separate out one-fiftieth, and this is called the terumah gedolah [the "great gift-offering"], and one gives it to a priest. About this it is said in the Torah, (Deut. 18:4) You shall also give him the first fruits of your new grain and wine and oil. Afterwards, one separates from the remainder one-tenth, and this is called ma'asér rishon [the "first tithe"], and one gives it to a Levite. About this it is said in the Torah, (Num. 18:24) For it is the tithes set aside by the Israelites [as a gift to the LORD hat I give to the Levites as their share], and (Num. 18:21) To the Levites I hereby give all the tithes in Israel.
Halacha 3ג׳
וְאַחַר כָּךְ מַפְרִישׁ מִן הַשְּׁאָר אֶחָד מֵעֲשָׂרָה וְהוּא הַנִּקְרָא מַעֲשֵׂר שֵׁנִי. וְהוּא לִבְעָלָיו וְאוֹכְלִין אוֹתוֹ בִּירוּשָׁלַיִם. וְעָלָיו נֶאֱמַר (ויקרא כז לא) "וְאִם גָּאל יִגְאַל אִישׁ מִמַּעַשְׂרוֹ". וְעָלָיו נֶאֱמַר (דברים יד כב) "עַשֵּׂר תְּעַשֵּׂר" (דברים יד כג) "וְאָכַלְתָּ לִפְנֵי ה' אֱלֹהֶיךָ בַּמָּקוֹם אֲשֶׁר יִבְחַר":
Afterwards, one separates from the remainder one-tenth, and this is called ma'asér sheni [the "second tithe"], and this is for the owner to eat in Jerusalem. About this it is said, (Lev. 27:31) If anyone wishes to redeem any of his tithes, [he must add one-fifth to them], and about this it is said, (Deut. 14:22-23) You shall set aside every tenth year [of all of the yield of your sowing that is brought from the field.] You shall consume the tithes [of your new grain and wine and oil, and the firstlings of your herds and flocks, in the presence of the LORD your God, in the place where He will choose to establish His name, so that you may learn to revere the LORD your God forever].
Mishneh Torah, Torat Emet 363 edition, via Sefaria — public domain
English: Gifts for the Poor, tr. Joseph B. Meszler, 2003 — CC BY