Is it obligatory for someone who wants to enjoin another person to the good or forbid him from evil to have…

Answer

Whoever enjoins and forbids must know what the good and evil are and knows that the wrongdoer commits them intentionally and without any shar‘ī excuse. It is obligatory to enjoin the good and forbid evil only when it is likely to be effective and one is secure from harm in doing it, considering the extent of the expected harm and the importance of the good or evil in question. Otherwise, it is not obligatory for him.