A summary of the fundamental concepts of Ahl al-Sunnah:
Environment inevitably shapes the nature and characteristics of knowledge.
Because the people of the Hijaz were close to the cradle of divine revelation,
and the novel events and unprecedented occurrences among them were relatively limited,
the school of Ahl al-Hadith rose to prominence among them.
Consequently, exegetes and hadith scholars who relied directly on transmitted reports flourished there;
they adhered most strictly to the texts of revelation
and to the traditions of the Companions and the Tabi'un.
By contrast, because Iraq was a land of division and divergent sects,
afflicted with the Rawafid and the theological denial of divine decree (Qadar),
and saw extensive translation of philosophers and scholastic theologians,
alongside widespread interaction with non-Arabs,
numerous novel issues and complex situations arose
that had no parallel in the Hijaz.
When all this took place, the school of reasoned opinion (Ahl al-Ra'y) emerged,
leading to an increased reliance on analogical deduction (qiyas) and ijtihad to rule on emerging events and unprecedented cases
concerning which no explicit scriptural text existed.
The Levant (al-Sham), on the other hand, was a land of jihad and frontier garrisoning (ribat);
thus, discourse concerning epic battles and tribulations became prominent among its people and scholars.
Just as the environment shapes knowledge, it also profoundly influences the scholar himself,
at times even shifting some of his legal opinions and scholarly deductions (ijtihad).
For instance, Imam al-Shafi'i had two distinct legal doctrines:
one formulated in Iraq, and the other developed in Egypt.