Hadith 10-1

حَدَّثَنا عَلِىُّ بْنُ عَبْدِ اللَّه الوَرَّاقُ رَضِىَ اللهُ عَنْهُ قالَ: حَدَّثَنا سَعْدُ بْنُ عَبْدِ اللَّه قالَ: حَدَّثَنا أَحْمَدُ بْنُ أَبي عَبْدِ اللَّهِ البَرْقِيُّ، عَنْ أَبيهِ، عَنْ رَبِيعِ بْنِ عَبْدُ الرَّحْمنِ قالَ: كانَ وَاللَّهِ مُوسَى بْنِ جَعْفَرٍعَلَيْهِمَا السَّلاَمُ مِنَ المُتَوَسِّمِينَ، يَعْلَمُ مَن يَقِفُ عَلَيْهِ بَعْدَ مَوْتِهِ وَيَجحَدُ الإِمامَ بَعْدَ إِمامَتِهِ، فَكانَ يَكظِمُ غَيظَهُ عَلَيْهِمْ و لا يُبدِي لَهُم ما يَعرِفُهُ مِنْهُمْ فَسُمِّي الكاظِمِ لِذلِكَ.

Ali ibn Abdillah al-Warraq - may God be pleased with him - narrated that Sa’d ibn Abdillah quoted on the authority of Ahmad ibn Abi Abdillah al-Barqi, on the authority of his father, on the authority of Rabi ibn Abdurrahman, “I swear by God that Musa ibn Ja'far (a.s.) was extremely intelligent. He knew those who will stop believing in Divine Leadership after him, and not accept the next Divine Leaders. However, he (a.s.) quenched his anger and did not divulge what he (a.s.) knew about them. That is why he (a.s.) is called 'Kazim. [2] “