Abu Rifa reported,

I came to the Prophet ﷺ while he was delivering a sermon and said, "A stranger has come asking about his religion, for he does not know what his religion is."The Prophet turned to me and left his sermon. Then a chair was brought whose legs were of palm fiber, though they appeared to be iron, and the Messenger of Allah ﷺ sat upon it. He then turned to me and began teaching me from what Allah had taught him. Afterwards, he returned to his sermon and completed its remaining portion.Abu Abdul-Rahman said in his narration that Humayd said, "I think he saw black wood and assumed it was iron."

Ahmad 24009.62

Sahih

حدثنا هاشم بن القاسم وأبو عبد الرحمن المقرئ قالا: حدثنا سليمان بن المغيرة عن حميد بن هلال،

عن أبي رفاعة العدوي قال

أتيت النبي ﷺ وهو يخطب، فقلت: رجل غريب جاء يسأل عن دينه، لا يدري ما دينه. قال: فأقبل النبي، وترك خطبته، ثم أتي بكرسي خلب قوائمه حديد، فقعد عليه رسول الله ﷺ، ثم أقبل علي يعلمني مما علمه الله، ثم أتى خطبته، فأتم آخرها. قال أبو عبد الرحمن في حديثه: قال حميد: قال أراه رأى خشبا أسود حسبه حديدا

أحمد 24009.62صحيح
Contents
Reference
Commentary
Ayat
Collection
Musnad Ahmad
Book
Abu Rifa Adawi
Numbering
Darussalam 24009.62
Ahmad24009. 24009.62