וְשָׂמַחְתָּ֞ לִפְנֵ֣י ׀ יְהוָ֣ה אֱלֹהֶ֗יךָ אַתָּ֨ה וּבִנְךָ֣ וּבִתֶּךָ֮ וְעַבְדְּךָ֣ וַאֲמָתֶךָ֒ וְהַלֵּוִי֙ אֲשֶׁ֣ר בִּשְׁעָרֶ֔יךָ וְהַגֵּ֛ר וְהַיָּת֥וֹם וְהָאַלְמָנָ֖ה אֲשֶׁ֣ר בְּקִרְבֶּ֑ךָ בַּמָּק֗וֹם אֲשֶׁ֤ר יִבְחַר֙ יְהוָ֣ה אֱלֹהֶ֔יךָ לְשַׁכֵּ֥ן שְׁמ֖וֹ שָֽׁם׃
At magsasaya ka sa harap ng Walang-Hanggan na iyong Diyos, ikaw, ang iyong anak na lalaki, ang iyong anak na babae, ang iyong aliping lalaki, ang iyong aliping babae, ang Levita na nasa iyong mga lungsod, at ang dayuhan, ang ulila, at ang balo na nasa gitna mo, sa lugar na pipiliin ng Walang-Hanggan na iyong Diyos upang doon patahanin ang Kanyang Pangalan.
Rashi
לוי גר יתום ואלמנה THE LEVITE THE STRANGER, THE FATHERLESS, THE WIDOW — these four are Mine, corresponding to four that are yours, viz., בנך ובתך ועבדך ואמתך THY SON, THY DAUGHTER, THY MAN-SERVANT AND THY MAID-SERVANT; if you gladden Mine, I will gladden yours (Midrash Tanchuma, Re'eh 18).
Ramban
He mentions here [that you are to rejoice] in the place which the Eternal thy G-d shall choose to cause His Name to dwell there,359Verse 11. and likewise he said, Three times in a year shall all thy males appear before the Eternal thy G-d in the place which He shall choose.360Verse 16. Now, I do not know whether this is to state that after the Sanctuary will be built we should not assemble to bring the festival-offerings except in that place which G-d has chosen, similar to what he said, Thou mayest not sacrifice the Passover-offering within any of thy gates,361Verse 5. And as the following verse continues but at the place which the Eternal thy G-d shall choose etc. or that he is explaining here that they are not obligated to go up in pilgrimage on the festivals until such time as G-d will have chosen the place to dwell there.362This would thus exclude the periods of Shiloh, Nob, Gibeon — before the building of the Sanctuary in Jerusalem — when the people were not obligated by law of the Torah to go up in pilgrimage on the festivals.
Sforno
והגר והיתום והאלמנה, they shall rejoice on the festival of cutting (the wheat). Their rejoicing will take the form of their collecting the portions of this harvest set aside for them by the Torah, i.e. the פאה, corner of the field with standing grain; the gleanings, what the farmer had overlooked, etc. These have been enumerated in connection with the festival in Leviticus 23,22.