Hadith on Curses: We viewed cursing our brothers as a major sin

Yazid ibn Abi ‘Ubayd reported: Salamah ibn al-Akwa’, may Allah be pleased with him, said, “If we saw a man curse his brother, we considered it as if he had come to a door of mortal sin.”

Source: al-Mu’jam al-Awsaṭ 6670

Grade: Sahih (authentic) according to Al-Albani

عن يَزِيد بْن أَبِي عُبَيْدٍ قَالَ قَالَ سَلَمَة بْن الْأَكْوَعِ رضي الله عنه كُنَّا إِذَا رَأَيْنَا الرَّجُلَ يَلْعَنُ أَخَاهُ رَأَيْنَا أَنَّهُ قَدْ أَتَى بَابًا مِنَ الْكَبَائِرِ

6670 المعجم الأوسط للطبراني

2791 المحدث الألباني خلاصة حكم المحدث صحيح في صحيح الترغيب