We have been taught by Rasulullah (Sallallaahu ‘alayhi wasallam), that on seeing a sick person, we should read a certain Dua, the blessings of which are such, that we will be protected from that same sickness.
So when we see a line of patients outside a hospital, or we visit the sick, we quietly read the Dua:
"All praise is due to Allah who has saved me from that with which He afflicted you and gave me excellence over most of whom He created."
When we see a line of people cueing up in front of a cinema, or engaging in sins, then these people are spiritually sick.
We should read the same Dua, and we should also express gratitude to Allah Ta’ala for protecting us – otherwise we too could be in those same sins.
Added to this, make sincere Dua that Allah Ta’ala grants Hidayah to these people
who are spiritually sick.
Just as we do not look down upon a person who is physically sick, we should not look down upon one who is indulging in sins. He is spiritually sick and in greater need of treatment and medication, than the patient with physical ailments.
 This Dua should not be read aloud, such that the person hears, since it could hurt his feelings.
 Hidayah: guidance