The 241st prohibition is that we are forbidden from taking a security deposit from a widow, regardless of whether she is rich or poor.
The source of this prohibition is G‑d's statement,1 "Do not take a widow's garment as security for a loan."
In the words of the Mishneh:2 "One may not take a security deposit from a widow, regardless of whether she is rich or poor, as the verse says, 'Do not take a widow's garment as security for a loan.' "
The details of this mitzvah are explained in the 9th chapter of tractate Bava Metzia.
