The Prophet ﷺ said, "It does not befit a truthful person to be one who frequently curses."
حدثنا منصور أخبرنا سليمان يعني ابن بلال عن العلاء عن أبيه
عن النبي ﷺ قال لا ينبغي للصديق أن يكون لعانا
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Its isnad is sahih. Sulayman bin Muhammad Abu Muhammad, the freed servant of the family of Siddiq, is a trustworthy imam. He narrated from Zayd bin Aslam and Abdullah bin Dinar, and his son Ayub, Qanabi, and Luwayn narrated from him. He died in the year 172.