As Islam spread across the world, the sahaba also set out from Madinah in the capacity of governors, judges, and teachers to teach Islam and settled down across various parts of Arabia. As people asked them questions about new issues that arose, they exercised their best judgment in understanding and deriving the ruling from the Qur’an and Sunnah as was the methodology mentioned in the hadith of Mu’adh. These leading companions had many students who in turn taught other students and this is how early schools developed.
