Tosefta for Psalms 136:21

וְנָתַ֣ן אַרְצָ֣ם לְנַחֲלָ֑ה כִּ֖י לְעוֹלָ֣ם חַסְדּֽוֹ׃

And gave their land for a heritage, For His mercy endureth for ever;