Proof that Imamat (leadership with Divine Authority) Continues in the Descendents of the Preceding Imam but not through his Brother or Paternal Uncle or other such Relatives
5 Aḥadīth
Hadith No. 1
Ali ibn Ibrahim has narrated from Muhammad ibn ‘Isa from Yunus from al-Husayn ibn Thuwayr ibn abu Fakhita from abu‘Abdallah 
who has said the following. “Imamat (Leadership with Divine Authority) will never go to two brothers after al-Hassan and al-Husayn . It has continued from Ali ibn al-Husayn as Allah, the Most Holy, the Most High has said, “The relatives are closer to each other, according to the Book of God, . .” (33:6) After Imam Ali ibn al-Husayn will only be found in the descendents one after the other.”
عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ مُحَمَّدِ بْنِ عِيسَى عَنْ يُونُسَ عَنِ الْحُسَيْنِ بْنِ ثُوَيْرِ بْنِ أَبِي فَاخِتَةَ عَنْ أَبِي عَبْدِ الله قَالَ لا تَعُودُ الامَامَةُ فِي أَخَوَيْنِ بَعْدَ الْحَسَنِ وَالْحُسَيْنِ أَبَداً إِنَّمَا جَرَتْ مِنْ عَلِيِّ بْنِ الْحُسَيْنِ كَمَا قَالَ الله تَبَارَكَ وَتَعَالَى وَأُولُوا الارْحامِ بَعْضُهُمْ أَوْلى بِبَعْضٍ فِي كِتابِ الله فَلا تَكُونُ بَعْدَ عَلِيِّ بن الحسين (عَلَيْهما السَّلام) إِلا فِي الاعْقَابِ وَأَعْقَابِ الاعْقَابِ.
Ali ibn Muhammad has narrated from Sahl ibn Ziyad from Muhammad ibn Walid from Yunus ibn Ya‘qub who has said that he heard abu ‘Abdallah say the following. “ Allah has disdained to place Imamat in two brothers after al-Hassan and al-Husayn .”
عَلِيُّ بْنُ مُحَمَّدٍ عَنْ سَهْلِ بْنِ زِيَادٍ عَنْ مُحَمَّدِ بْنِ الْوَلِيدِ عَنْ يُونُسَ بْنِ يَعْقُوبَ عَنْ أَبِي عَبْدِ الله أَنَّهُ سَمِعَهُ يَقُولُ أَبَى الله أَنْ يَجْعَلَهَا لاخَوَيْنِ بَعْدَ الْحَسَنِ وَالْحُسَيْنِ (عَلَيْهما السَّلام )
Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad ibn ‘Isa from Muhammad ibn Isma‘il ibn Bazi‘ who has said the following. “Abu al-Hassan al-Rida was once asked, “Can Imamat continue in uncles?” He replied, “No, it can not happen.” The narrator has said that he asked the Imams , “Can it continue in a brother?” He replied, “No, it can not happen.” I then asked, “With who then it can continues?” He replied, “It will continue with my children.” In those days he hadd no children.”
مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدِ بْنِ عِيسَى عَنْ مُحَمَّدِ بْنِ إِسْمَاعِيلَ بْنِ بَزِيعٍ عَنْ أَبِي الْحَسَنِ الرِّضَا أَنَّهُ سُئِلَ أَ تَكُونُ الامَامَةُ فِي عَمٍّ أَوْ خَالٍ فَقَالَ لا فَقُلْتُ فَفِي أَخٍ قَالَ لا قُلْتُ فَفِي مَنْ قَالَ فِي وَلَدِي وَهُوَ يَوْمَئِذٍ لا وَلَدَ لَهُ.
Muhammad ibn Yahya has narrated from Muhammad ibn al Husayn from ‘Abd al-Rahman ibn abu Najran from Sulayman ibn Ja‘fari from Hammad ibn ‘Isa from abu ‘Abdallah who has said the following. “Imamat (Leadership with Divine Authority) does not take place in two brothers after al-Hassan and al-Husayn . It only continues in the descendents of the Imam generation after the generation.”
مُحَمَّدُ بْنُ يَحْيَى عَنْ مُحَمَّدِ بْنِ الْحُسَيْنِ عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي نَجْرَانَ عَنْ سُلَيْمَانَ بْنِ جَعْفَرٍ الْجَعْفَرِيِّ عَنْ حَمَّادِ بْنِ عِيسَى عَنْ أَبِي عَبْدِ الله أَنَّهُ قَالَ لا تَجْتَمِعُ الامَامَةُ فِي أَخَوَيْنِ بَعْدَ الْحَسَنِ وَالْحُسَيْنِ إِنَّمَا هِيَ فِي الاعْقَابِ وَأَعْقَابِ الاعْقَابِ.
Muhammad ibn Yahya has narrated from Muhammad ibn al-Husayn from ibn abu Najran from ‘Isa ibn ‘Abdallah ibn ‘Umar ibn Ali ibn abu Talib who has said that he asked abu ‘Abdallah the following. “Would there happen what is to happen, may Allah would not show me such a day (death of the Imam who then must I follow as my Imam?” The Imam pointed to his son Musa . The narrator has said that he asked the Imams , “ What if something will happen to Musa who then must I follow?” The Imam , “Follow a son.” I then asked, “What if something would happen to the son and the Imam would leave behind an elder brother or a small son then who must I follow?” The Imam said, “Follow his son and so on one after the other.” In the script of Sawan it says, “. .and so on forever.”
مُحَمَّدُ بْنُ يَحْيَى عَنْ مُحَمَّدِ بْنِ الْحُسَيْنِ عَنِ ابْنِ أَبِي نَجْرَانَ عَنْ عِيسَى بْنِ عَبْدِ الله بْنِ عُمَرَ بْنِ عَلِيِّ بْنِ أَبِي طَالِبٍ عَنْ أَبِي عَبْدِ الله قَالَ قُلْتُ لَهُ إِنْ كَانَ كَوْنٌ وَلا أَرَانِي الله فَبِمَنْ أَئْتَمُّ فَأَوْمَأَ إِلَى ابْنِهِ مُوسَى قَالَ قُلْتُ فَإِنْ حَدَثَ بِمُوسَى حَدَثٌ فَبِمَنْ أَئْتَمُّ قَالَ بِوَلَدِهِ قُلْتُ فَإِنْ حَدَثَ بِوَلَدِهِ حَدَثٌ وَتَرَكَ أَخاً كَبِيراً وَابْناً صَغِيراً فَبِمَنْ أَئْتَمُّ قَالَ بِوَلَدِهِ ثُمَّ وَاحِداً فَوَاحِداً. وَفِي نُسْخَةِ الصَّفْوَانِيِّ ثُمَّ هَكَذَا أَبَداً.