What is the recompense for one who afflicts people with the evil eye unintentionally, while observing his obligatory duties and supererogatory acts, and will he be held accountable for that on the Day of Resurrection without any good deeds?

A Muslim is not permitted to harm his brother with the evil eye. The harm of the evil eye can come from a loved one or an enemy. Whoever admires something should immediately invoke blessings upon it.

Many scholars are of the opinion that the person who casts the evil eye must be restrained and prevented from associating with people to avert harm. Some of them are of the opinion that he should be held liable for what he has damaged. So, if the one who casts the evil eye damages something, he is liable for it. If he kills, there is no qisas (retaliation in kind), no diyah (blood money), and no kaffarah (expiation) according to the Shafi'i school, because it does not usually lead to death.

As for his punishment in the hereafter, that is part of the unseen. However, if he intentionally afflicts creatures with his evil eye, then he will have caused himself severe torment if he does not repent.