And whoever is helped after he is wronged, then there is no way to take action against them.
“Upon them” means upon the believers. That is, being part of self-defense by the one who has undergone injustice, or being part of helping him by others, if the wrongdoer inflicts any evil or distress, the believers are not to take action against the one who is wronged and those who helped him.
When the Messenger said, “Help the wrongdoer and the one who is wronged,” the companions asked: “We know how to help the one who is wronged, but how is it possible to help the wrongdoer?” The Messenger replied: “It is to restrain the wrongdoer from his injustice.” Since there is no group of believers anywhere in the world, the only way to restrain people from the Satanic deeds and influences—as explained in verses 2: 168-169—is to propagate Adhikr among mankind and familiarize the Lord Allah to them, and, by quoting verses 17: 13-14 which say that “each individual is bearing his/her Book of deeds around his/her neck which will be given to him/her on the Day of Judgement as an illuminated open book, and it will be said to him/her: ‘You read your Book; you are enough for doing your reckoning this Day,’” make them aware that all deeds, words, as well as thoughts of each individual after the age of fifteen are being inscribed in that Book. See explanation 4: 135; 17: 36 and 41: 19-24.