Why Are There Four Schools of Islamic Law?

The short answer is above. What follows is the reasoning behind it, including where scholars differed.

The evidence

Differences arise from whether a hadith reached an imam, how a text is interpreted, the strength given to the practice of Madinah, analogy, and the wording of Arabic itself.

The four imams each stated that their views should be abandoned where a sound hadith contradicts them.

The schools agree on the pillars of faith and worship; disagreement concentrates in details of practice.

In practice

• Following a school is a way of accessing scholarship, not a rejection of evidence.
• Do not select rulings across schools to assemble the easiest version of each question.
• Learn one school properly rather than fragments of four.

Knowledge that is not acted on has a name in the tradition, and it is not a flattering one. Pick the smallest applicable step.

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