Grading of the chain: This chain is "da'if" because Abu al-Yaqzan 'Imran bin 'Abd Allah is "majhul" (unknown). This report is also narrated through two other routes from Rabi'ah al-Sa'di (Ibn Shayban Abu al-Hawra'), but both of them are "wahi jiddan" (extremely weak), while the author's route is far better (amthal) than them. Al-Dhahabi cited this narration of the author in "Siyar A'lam al-Nubala'" (in the biography of Khadijah, 2/116) and said: "There is softness (lin) in its chain."

Identification of narrators: Muhammad bin Ja'far is "al-Faydi", and Sa'id bin 'Ajab is "Sa'id bin 'Abd Allah bin Muhammad bin 'Ajab"; here he is attributed to his great-grandfather.

Takhrij / Reference: Ibn 'Asakir narrated it in "Tarikh Dimashq" (14/172-173) within a long hadith, by way of Shu'ayb bin Mahan, from 'Amr bin Jumay' al-'Abdi, from 'Abd Allah bin al-Hasan bin al-Hasan bin 'Ali, from Rabi'ah al-Sa'di, from Hudhayfah.
Grading of the chain: Its chain is "talif" (ruined), because 'Amr bin Jumay' is "matruk and accused (muttaham)".

Takhrij / Reference: Abu Ya'la in "al-Musnad al-Kabir" (as cited in "Jami' al-Masanid" 2122 and "al-Matalib al-'Aliyah" 4095) narrated from Sulayman bin Dawud al-Shadhakuni, from Isma'il bin Aban, from 'Atiyyah bin Ya'la, from 'Abd al-Rahman bin Yazid (of the descendants of Abu Hurayrah), from al-Dahhak al-Bunani, from Rabi'ah al-Sa'di, from Hudhayfah bin al-Yaman, from the Messenger of Allah (peace and blessings be upon him), who said: "... and Khadijah bint Khuwaylid is the first of the Muslim women to accept Islam."
Grading of the chain: This chain is utterly "talif" (ruined). Al-Shadhakuni and Isma'il bin Aban (al-Ghanawi al-Kufi) are both "matruk and accused". 'Atiyyah bin Ya'la was declared weak by Abu al-Fath al-Azdi, while al-Dahhak al-Bunani and 'Abd al-Rahman bin Yazid are "majhul".

More authentic narration: More authentic than this report is the hadith of 'A'ishah (may Allah be pleased with her), which Ahmad (21/24864) and al-Tabarani in "al-Kabir" (23/21) and others narrated through two routes, that the Messenger of Allah (peace and blessings be upon him) said about Khadijah: "She believed in me when people disbelieved, and she affirmed me when people belied me." Al-Tabarani's chain is "hasan".