Amr Bil Ma'ruf and Nahi 'Anil Munkar (enjoining good and forbidding wrong) is a topic which can be taken well among brothers and sisters, and also a topic which is highly ignored. It is important that as Muslims who believe that these two acts are a part of our practice, we make sure we are able to find a balance and execute these two obligations actions correctly.
Yes, as Muslims, we are taught what is right and wrong, and we should use the ability to know the difference between the two, to decide what is good and bad. But, one should not be too quick to judge as to hurt another brother or sister's feelings, which is definitely not allowed in Islam.
Like any other obligatory deed, Amr Bil Ma'ruf and Nahi Anil Munkar have conditions and regulations governing them. For example, we may use words to fulfill this obligation, and even physical force in some cases, but if the individual still does not heed our warning, we are absolved of the obligation.
The Holy Prophet Muhammad (peace be upon him and his progeny) has said: "The one who sees a wrong action done should prohibit it by his deed, if he is capable, of course; and if he cannot do that, he should prohibit it by his tongue, but if he is not able to do even that, he may forbid it by his heart." (Wasail al-Shia)
It is important to also keep in mind that we must enjoin and forbid as often as we can. If we turn a blind eye to wrongs, and if we do not encourage our brothers and sisters to do good, then we are being selfish. Islam is not a religion of selfishness and only caring about ourselves – rather, it is a religion of community and brotherhood in which we strive together and try our best to keep the religion alive and respected. If Muslims do not act on these guidelines provided by our Holy Prophet and Ahlul Bayt (peace be upon them), then the goals of Islam will be misunderstood.
When believers work together, are conscious of each others' feelings, and are aware of each others' weaknesses and strengths, then as a community we can prosper. Wrong things cannot take place because people work together to make sure that the right way of, for example, conducting business takes place. As Imam Muhammad al-Baqir (peace be upon him) said: "Verily, enjoining what is right and forbidding what is wrong is the way of prophets and the method of good doers. It is such a great obligatory deed by which other obligatory deeds can survive, other creeds can be saved, bargains are lawful, injustices are warded off, and prosperity can fill the earth." (Al-Kafi)
Imagine a community of people in which everyone had each other's backs. Nobody was out to hurt another, yet people were out to make sure everyone was doing good. Rather than people trying to cheat each other or go on ego trips, people would work together to foster a good, Islamic environment in which the ways of the Holy Prophet are followed.
It is important that we realize we need to keep a balance in our judgments. Yes, we are "nobody to judge", as we know God is the Ultimate Judge – but we also need to keep in mind that God gave us a beautiful religion with clear guidelines of right and wrong, in which we should also use our God-given logic to make a realization, and/or judgment of what we should or should not be doing, who we should or should not be hanging out with, and what we should or should not be saying, etc. We also cannot be on the other extreme of only judging and condemning everyone to hell, or of being hypocrites, just because in our eyes they do not do things the way "I" do it, or they do not go to the mosque as often as "I" do, or they do not wear hijab exactly the way "I" do. Islam is a religion of tolerance and understanding, and that is what takes us far and beyond to reach greater goals.
Just as the Holy Prophet loved and helped every human, we should follow suit – not judging anyone, but being compassionate and loving with everyone in order to work together to become better by sharing our knowledge of what is right and wrong in the kindest and gentlest of manners.