When. On seeing someone in the grip of an affliction — an illness, a disability, a visible ruin. It belongs to the moment of looking, which is the moment the heart is most likely to produce something ugly instead: pity that flatters the one who feels it, or relief that does not know its own name.
Say it quietly. This is the supplication's first condition of use, and it is transmitted with it: it is said under the breath, not where the afflicted person can hear. Words that comfort the speaker can wound the one they are spoken over. A supplication said loudly here would do the exact damage it was meant to prevent.
The words. 'Afani is from 'afiya, wellbeing — a root whose older sense is effacement, the wiping away of a trace. Al-'afiya is therefore not a strong body but the absence of harm, a subtraction rather than a possession, which is why it goes unnoticed until it goes. Ibtala is from bala', trial and testing, and it is deliberately not the vocabulary of punishment. What the onlooker sees is called a test, not a sentence, and that single word choice forbids the conclusion the eye reaches for.
Many, not all. 'Ala kathirin mimman khalaq — over many of those He created, not over all of them. The wording stops short of a claim of rank. It says only that a share of ease has landed here and not there, and offers no explanation of why, because the speaker has none.
Its opposite number. The refuge sought in the morning from serious illness is the same subject seen from inside the fear; this one is that subject seen from safety.