Abdullah bin Masud reported,

The Messenger of Allah ﷺ sent us to the Negus, and we numbered around eighty men, among them Abdullah bin Masud, Jafar, Abdullah bin Urfutah, Uthman bin Mazun, and Abu Musa. They came to the Negus, and Quraysh sent Amr bin As and Umarah bin Walid bearing a gift.When the two Qurayshis entered upon the Negus, they prostrated to him, then hurried to his right and left sides and said to him, "A group of our cousins have settled in your land. Send for them."So he sent for them.Jafar said to his companions, "I will be your spokesman today, so follow my lead." He greeted the Negus but did not prostrate.They asked him, "Why do you not prostrate to the king?"Jafar replied, "We prostrate only to Allah ."The Negus asked, "Why is that?"He said, "Allah sent us His Messenger ﷺ and commanded us not to prostrate to anyone but Allah , and He commanded us to perform the prayer and give the alms."Amr bin As said, "But they differ with you concerning Isa bin Maryam!"The Negus asked, "What do you say about Isa bin Maryam and his mother?"They answered, "We say what Allah said about him. He is the Word of Allah and His Spirit, which He cast into the Virgin, untouched by any man and never approached by any child."The Negus picked up a stick from the ground and said, "People of Abyssinia, priests and monks, by Allah, they do not add to what we say about him so much as the weight of this stick. Welcome to you, and to the one from whom you have come. I bear witness that he is the Messenger of Allah, for he is the one we find described in the Gospel, and he is the messenger whom Isa bin Maryam announced. Settle wherever you wish. By Allah, were it not for the kingship I am occupied with, I would go to him myself until I were the one carrying his sandals and pouring water for his ablution."He ordered that the gift of the others be returned to them.Then Abdullah bin Masud hastened back and reached Badr in time, and he said that the Prophet ﷺ sought forgiveness for him when news of his death reached him.

عن ابن مسعود قال

بعثنا رسول الله ﷺ إلى النجاشي، ونحن نحو من ثمانين رجلا، فيهم عبد الله بن مسعود، وجعفر، وعبد الله بن عرفطة، وعثمان بن مظعون، وأبو موسى، فأتوا النجاشي، وبعثت قريش عمرو بن العاص وعمارة بن الوليد بهدية، فلما دخلا على النجاشي سجدا له، ثم ابتدراه عن يمينه وعن شماله، ثم قالا له: إن نفرا من بني عمنا نزلوا أرضك، فابعث إليهم، فبعث إليهم، فقال جعفر: أنا خطيبكم اليوم فاتبعوه، فسلم ولم يسجد، فقالوا له: مالك لا تسجد للملك؟ قال: إنا لا نسجد إلا لله عز وجل قال: وما ذلك؟ قال: إن الله عز وجل بعث إلينا رسوله ﷺ وأمرنا أن لا نسجد لأحد إلا لله عز وجل وأمرنا بالصلاة والزكاة، قال عمرو بن العاص: فإنهم يخالفونك في عيسي بن مريم! قال: ما تقولون في عيسى ابن مريم وأمه؟ قالوا: نقول كما قال الله عز وجل، هو كلمة الله وروحه، ألقاها إلى العذراء البتول التي لم يمسها بشر، ولم يفرضها ولد، قال: فرفع عودا من الأرض، ثم قال: يا معشر الحبشة والقسيسين والرهبان، والله ما يزيدون على الذي نقول فيه ما يسوى هذا؟ مرحبا بكم، وبمن جئتم من عنده، أشهد أنه رسول الله، فإنه الذي نجد في الإنجيل، وإنه الرسول الذي بشر به عيسي ابن مريم، انزلوا حيث شئتم، والله لو لا ما أنا فيه من الملك لأتيته حتى أكون أنا أحمل نعليه، وأوضؤه. وأمر بهدية الآخرين فردت إليهما، ثم تعجل عبد الله بن مسعود حتى أدرك بدرا، وزعم أن النبي ﷺ استغفر له حين بلغه موته.