Hazrat Ja’far (radhiyallahu ‘anhu) mentions, “We departed from Abyssinia, and on arriving in the blessed presence of Rasulullah (sallallahu ‘alaihi wasallam) in Madinah Munawwarah, he hugged me and exclaimed, ‘I do not know if I am more pleased over the conquest of Khaibar or the arrival of Hazrat Ja’far (radhiyallahu ‘anhu).’”

Rasulullah (sallallahu ‘alaihi wasallam) then sat while the messenger of Najaashi stood and said, “(O Rasul of Allah (sallallahu ‘alaihi wasallam)!) Hazrat Ja’far (radhiyallahu ‘anhu) is here before you. Ask him how our Emperor had received him and treated him.”

Hazrat Ja’far (radhiyallahu ‘anhu) replied, “Undoubtedly, Najaashi welcomed us and treated us in such-and-such manner. In fact, he showed us such kindness that when we departed from Abyssinia, he even provided us with conveyances and provisions for the journey. He offered us his constant assistance. He also testified that there is none worthy of worship besides Allah and he testified that you are certainly the messenger of Allah (sallallahu ‘alaihi wasallam). He requests that you make du‘aa for his forgiveness.”

Rasulullah (sallallahu ‘alaihi wasallam) immediately stood, performed wudhu and made the following du‘aa thrice:

اللهم اغفر للنجاشي

O Allah! Forgive Najaashi!

Hearing this du‘aa, all the Sahaabah (radhiyallahu ‘anhum) said ameen.

Hazrat Ja’far (radhiyallahu ‘anhu) mentions, “I then said to the messenger of Najaashi, ‘When you return to Abyssinia, then describe to Najaashi what transpired and how Rasulullah (sallallahu ‘alaihi wasallam) made du‘aa for him.’”

(Extracted from Seeraul Mustafa 1/257-258)