Narrated Saeed ibn Zayd: The Prophet ﷺ said: The most prevalent kind of usury is going to lengths in talking unjustly against a Muslim's honour.
Explanation & Benefits
Shaykh Umar Farooq Saeedi
Benefits and Issues:
Just as usury (riba) is forbidden in commercial transactions, in the same way, dishonoring and disrespecting your Muslim brother is also forbidden.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 4876