And He, the Exalted, also says:

“Alif–Lām–Mīm. Do people imagine that they will be left to say, ‘We believe,’ without being put to the test? We certainly tried those who came before them, so Allah will surely make known those who are truthful and He will surely make known the liars. Or do those who commit evil deeds think they can outstrip Us? How evil is the judgment they make.” (29:1–4)

A fitnah is an examination and a test, as Moses, peace be upon him, said:

“It is nothing but Your trial; by it You lead astray whom You will and guide whom You will.” (7:155)

That is: it is Your examination and testing—through it You cause to stray whoever opposes the messengers, and through it You guide whoever follows them.

The trial a human being undergoes is like the assaying of gold when it is placed in the furnace: the process separates what is fine from what is base. The truth resembles pure gold; the more it is tested, the more excellent it becomes. Falsehood is like a bright-looking yet alloyed metal: once tried, its corruption is laid bare.

Thus, the true religion—whenever an inquirer studies it or a debater defends it—its proofs appear in full clarity, certainty is strengthened by it, the believers’ faith increases, and its light shines in the hearts of humankind.

As for the false religion, whenever a polemicist argues on its behalf and tries to prop up its crooked staff, Allah, blessed and exalted, raises up someone who hurls the truth against falsehood.