It was narrated to my by my father ; who said – it was narrated to us by Saʿd bin ʿAbd Allāh, who said – it was narrated to us by Ibrāhīm ibn Hāshim, from ʿAlī bin Muʿbid, from al-Ḥussain bin Khālid, from ʿAlī bin Mūsa al-Ridha, from his father, from his forefathers, from ‘Amīr al-Mu’minīn عليه السلام who said:

The Messenger of Allāh صلى الله عليه وآله said: “Whosoever does not believe in my pond1, then Allāh will not lead him to my pond; and whosoever does not believe in my intercession, then Allāh does not extend my intercession to him.”
He صلى الله عليه وآله then said: “My intercession is limited to only those within my nation (ummah) who commit great sins; and as for those who are doers of good (al-Musanīn), there is no difficulty upon them.”
Al-Ḥussain bin Khālid said: “Oh son of the Messenger of Allāh, then what is the meaning of the words of Allāh, Mighty and Majestic: {and they cannot intercede except on behalf of one whom He approves?}2

1. The pond of al-Kawthar, gifted to the Prophet صلى الله عليه وآله, see Qur’ān 108
2. Al-‘Anbiyyā’ (21:28)

حدثنا أبي (رحمه الله)، قال: حدثنا سعد بن عبد الله، قال: حدثنا إبراهيم ابن هاشم، عن علي بن معبد، عن الحسين بن خالد، عن علي بن موسى الرضا، عن أبيه، عن آبائه، عن أمير المؤمنين عليهم السلام، قال: قال رسول الله (صلى الله عليه وآله): من لم يؤمن بحوضي فلا أورده الله حوضي، ومن لم يؤمن بشفاعتي فلا أناله الله شفاعتي، ثم قال (صلى الله عليه وآله): إنما شفاعتي لأهل الكبائر من أمتي، فأما المحسنون فما عليهم من سبيل. قال الحسين بن خالد: فقلت للرضا (عليه السلام): يا بن رسول الله، فما معنى قول الله عز وجل: ﴿ولا يشفعون إلا لمن ارتضى﴾؟ قال: لا يشفعون إلا لمن ارتضى الله دينه