Mishneh Torah — Negative Mitzvot מצוות לא תעשה, Chapter 233
The full Hebrew text of Mishneh Torah, Negative Mitzvot, Chapter 233, with English translation by Maimonides (Rambam).
שלא לשלח עבד עברי ריקם כשייצא חופשי, שנאמר "לא תשלחנו, ריקם" (דברים טו,יג).
Not to send away a Hebrew servant empty-handed when he goes free, as [Deuteronomy 15:13] states: "Do not send him away empty-handed."