Rely on the witness of the phenomenal world; to know whether you are on the mark or have gone astray:

Neither kingship nor poverty for a Muslim who lacks in faith, the one who has it is a king even if he be poor.

He depends on the sword if he lacks in faith: If he has faith he may need no weapons in the fight.

A Muslim without faith yields to what his fate ordains; with faith, he is destiny incarnate.

I revealed the secrets and rent the veil, but your blindness has no cure.