What should I do with a colleague who frequently curses my mother using foreign words, and should I leave him or instigate a problem with him?

It is permissible for one who has been wronged to supplicate against the oppressor, or to openly declare the harm that befell them, provided they do not exceed the scope of their grievance or transgress against anyone other than their oppressor. However, pardoning the wrongdoer is better. Retaliating to an evil deed with a similar one is permissible, but forgiveness and overlooking are preferable, and patience and pardon are among the most resolute of affairs. The wrongdoer should be dealt with through advice and gentleness, and a good response should be a cause for transforming enmity into alliance. It is not permissible to curse the parents of the wrongdoer if he curses your parents; rather, only he should be cursed, because every soul is pledged to what it has earned, and no bearer of burdens will bear the burden of another. Furthermore, prohibitions by their very nature, such as slander, cannot be retaliated against in kind.