All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ʻalayhi wa sallam, is His slave and Messenger.
The basic principle as far as the obligation of forbidding evil is concerned is that it is a communal obligation (required of the Muslims collectively; if some carry it out, the burden is waived from the rest). However, this obligation may be required of a certain person in certain situations.
“Enjoining good and forbidding evil is a collective obligation whereby if it is carried out by some people, then the others are exempted from it. However, if all of them neglected it, then everyone who is able to carry it out but neglected it without a valid excuse or fear of incurring considerable harm is sinful. There are cases in which an individual is obliged to enjoin good and forbid evil, such as if he is the only one who knows about the evil or if no one other than him can change it, or someone witnessing his wife, child, or servant committing a sin or neglecting a religious obligation.” [Sharh Saheeh Muslim]
The fact that the person is in his house and will have to take the lift to go down and the like does not waive the obligation of forbidding the evil.
Al-Aadaab Ash-Sharʻiyyah reads, “Chapter on forbidding evil in the marketplace: Ibn Al-Jawzi said, ‘If a person knows with certainty that a sin is constantly being committed in the market or at certain times and he can change it, it is impermissible for him to stay at home and neglect this obligation; rather, he is obliged to go to the market, forbid this evil, and change it, or part of it, if he can do so.’”
We would like to highlight two points in this regard:
First, the most likely correct view is that it is not incumbent to forbid the widespread evils when it is difficult or rather impossible to forbid all those who commit them, especially if it is believed that these sinners will most likely reject the advice and refrain from acting upon it. This warrants waiving the obligation of forbidding the evil according to many scholars.
Ibn ʻUthaymeen said:
“Some evils are extensively widespread and obvious to all people; is the Muslim obliged to forbid each and every one whom he witnesses committing them? For instance, shaving the beard is quite widespread among men now, and everyone knows that it is prohibited. Am I obliged to forbid each and every beardless man who passes by me from this evil? This is difficult because it is a well-known evil. The same goes for smoking. As for the evils which are neither obvious nor well-known to all people, I am obliged if I see someone committing them to forbid him. The first kind, which is the well known widespread evils, forbidding them depends on the person's ability to do so. If you sit with him for a meal or a drink or the like, you should give him advice about it, even if that evil is widespread and well known to people. But passing by him in the market and stopping him to say: ‘Listen here, this is a sin,’ you are not obliged to do that.”
Second, it is not prescribed to forbid someone from doing an act that is open for Ijtihaad (reasoning by qualified scholars) wherein there are different scholarly views that do not contradict an explicit religious text or consensus of scholars.
An-Nawawi wrote, “Scholars unanimously agreed that it is prescribed to forbid the acts that are known by consensus to be sinful. As for the matters about which scholars differed, it is not prescribed to forbid others from them. However, if one wishes to recommend to another by way of advice in order to avoid the scholarly difference of opinion, then this is a recommended and good thing to do provided that he does so gently.”
Some scholars even stated that it is impermissible to forbid a matter that is open for Ijtihaad.
Al-Aadaab Ash-Sharʻiyyah reads, “It is impermissible to forbid someone from doing a subsidiary matter open for Ijtihaad, whether that person practices Ijtihaad himself or follows the opinion of a mujtahid (qualified scholar who practices Ijtihaad) in this regard. This was highlighted by Al-Qaadhi and the scholars of our school of Fiqh (Hanbali)...”
Isbaal (letting the garment reach below the ankles) that is not done by way of pride is one of the matters open for Ijtihaad, and, hence, it is not prescribed to carry out forbidding evil regarding it.
Allah knows best.