{But that the works of God should be made manifest in him}
(all' hina phaner(9374)h(8869) ta erga tou theou en aut(9369)). Jesus
denies both alternatives, and puts God's purpose (all' hina
with first aorist subjunctive of phanero(935c)) as the true
solution. It is sometimes true that disease is the result of
personal sin as in the man in  5:14  and parents can hand on the
effects of sin to the third and fourth generations, but there are
cases free from blame like this. There is comfort for many
sufferers in the words of Jesus here.