ה֣וּא יַלְוְךָ֔ וְאַתָּ֖ה לֹ֣א תַלְוֶ֑נּוּ ה֚וּא יִהְיֶ֣ה לְרֹ֔אשׁ וְאַתָּ֖ה תִּֽהְיֶ֥ה לְזָנָֽב׃
He shall lend to thee, and thou shalt not lend to him; he shall be the head, and thou shalt be the tail.
Read midrashic interpretation of Deuteronomy 28:44: and classical rabbinic exegesis.