The ignorant person is the one who does not know the ruling and thus...

The ignorant person is the one who does not know the ruling and thus, we wish to teach him the ruling - for example a person who does not know the rulings in relation to backbiting. The ruling of Amr bil Ma'ruf and Nahi 'Anil Munkar is also something that is performed in regards to an issue in which the person is aware of the issue at hand and the rulings pertaining to it and is neither negligent of it, nor is he ignorant.

With this said, the question arises that what is the ruling of each of these? In relation to a person who is negligent and inattentive, if the issue is not so important such as the eating of something which is najis (ritually impure), then it is not wajib (obligatory) to remind that person; thus this issue is only limited to those important tasks, for example, shedding the blood of an innocent person thinking that he is a sinner (one for whom the death penalty has been specified for in Islam and must therefore be killed after going through the judicial procedure).

The person who is ignorant to the rulings must be taught them and this act is a wajib (obligatory) one. In relation to Amr bil Ma'ruf and Nahi 'Anil Munkar in which a person knowingly and intentionally performs a sin, we must command him to good and prevent him from committing evil through the use of kind words. Thus, each of these three acts is wajib (obligatory), however their scope is quite different from one another.

That which is normally seen among the common population is that they say “Let Musa be on his own faith and 'Isa be on his own faith” (meaning that we should not interfere with other people or pry into their lives) or some people say that, “You are not going to be in my grave” (so then do not tell me what to do and what not to do) but these are all words which have absolutely no meaning. We must guide one another and not be indifferent to this issue.

iIt is not equivalent to interfering in the lives of other people. Rather, it has been mentioned in the traditions that the example of a person who lives among a group of sinners is similar to a person who is sitting in a boat in his own area and drills a hole in the bottom of the boat. When other people start to ask him what he is doing he replies, “I am making a hole in my part of the boat” to which the people reply to him, “We all share the same eventual outcome.