Negative commandment · Lo Ta’aseh #256 of 613
Not to oppress any widow or orphan
שלא לענות יתום ואלמנה
The verse · Shemot 22:21
כׇּל־אַלְמָנָה וְיָתוֹם לֹא תְעַנּוּן
“You shall not afflict any widow, or fatherless child.”
The Rambam’s words
Not to oppress any widow or orphan, as [Exodus 22:21] states: "Do not oppress any widow or orphan."
שלא לענות יתום ואלמנה, שנאמר "כָּל אַלְמָנָה וְיָתוֹם לֹא תְעַנּוּן" (שמות כב, כא).
Who & when
“And this commandment is practiced in every place and at all times by males and by females, that all people are obligated to treat them gently and honorably.”
Where in the Mishneh Torah
Hilchot Human Dispositions הלכות דעות