In this verse of the Qur'an, "Let there be a community among you who call to the good, and enjoin the right, and forbid the wrong. They are the ones who have success" (Surah Al 'Imran: 104), Allah announces that He has made the faithful responsible for summoning people to virtue and rescuing them from the errors in which they find themselves. Consider another verse:
The men and women of the believers are protectors of one another. They command what is right and forbid what is wrong, and perform prayer and give the alms, and obey Allah and His messenger. They are the people on whom Allah will have mercy. Allah is Almighty, All-Wise. (Surat at-Tawba: 71)
Here, Allah points out that they have the duty of protecting and watching over one another.
In line with this instruction of Allah, the faithful point out the defects they see in one another in the way laid down by the Qur'an, that is, by "only saying the best" (Surat al-Isra': 53). The believer who provides an invitation to virtue has no responsibility for the reaction of the other party or whether he agrees with the advice given. Allah points out this truth in the verse, "You cannot guide those you would like to, but Allah guides those He wills. He has best knowledge of the guided" (Surat al-Qasas: 56).
He reminds us that people can see the truth only through His will. For this reason, while the faithful try to instruct one another in virtue and protect each other from evil, they do this by asking it from Allah and submitting to Him in whatever the outcome may be. Even so, they wish most ardently for everyone to know and live the beauty and true happiness that sincerity brings.
The faithful know that a life lived in a contrary fashion may appear normal, but is truly filled with corrosive torments that ruin the human soul. They are aware, too that these insincere people bring great material and moral harm upon themselves by concealing the unseemly ideas and spiritual state they experience. For this reason, if a believer feels even a trace of insincerity in another, he simply invites that person to the morality of the Qur'an without judging him in any way. He reminds him that to all types of secret sorrow and trouble, lack of tranquility and unhappiness, the sole solution is to live out a morality approved by Allah.
