Answered by Shaykh Faraz A. Khan
Question: I struggled to make sure a teacher at our Islamic school dressed modestly, since she teaches teenage boys. Was I being nosy?
Answer: Assalamu alaikum wa rahmatullah,
I pray this finds you in the best of health states. May Allah bless you for your efforts and desire to implement the Qur’an and Prophetic Sunna in your life.
No, you were not being nosy. You were fulfilling the communal obligation of commanding good and forbidding evil, a duty that is of utmost importance yet so often neglected today.
As for the hadith you cite, “From a person’s good and beautiful Islam is his leaving alone that which does not concern him,” it means one’s perfected practice of Islam entails his or her abstaining from all which is of no benefit, whether religious or worldly. [Sunan Tirmidhi; Mubarakpuri, Tuhfat al-Ahwadhi]
So the hadith does not refer to commanding good and forbidding evil, since that concerns every believer and is of benefit to oneself and others.
Indeed, Allah Most High states, “Let there be amongst you a group that invites to good, commands the good and forbids evil: those indeed are the successful ones.” (3:104)
And our Beloved Messenger (peace and blessings be upon him) said, “By the One in Whose hand is my soul, you will certainly command to good and forbid evil! Otherwise, Allah will soon enough send upon you tribulation from Him, after which you will call on Him yet your supplication will not be answered.” [Sunan Tirmidhi]
As for the conditions when it is obligatory to do so, please see the following:
And Allah knows best.
Checked & Approved by Faraz Rabbani