Is refraining from committing a sin out of fear of people's talk considered showing off (riyaa'), such as not bothering one's siblings to avoid people's talk, or not bothering anyone to avoid one's mother raising her voice?

Abandoning a sin for other than Allah—such as due to people's words and their condemnation—is considered hypocrisy (riya'), which Muhammad Mawlud al-Shinqiti defined in "Mutahharat al-Qulub" as "performing an act of worship for other than the Creator."

Abandonment (tark) is divided into three categories: that for which one is rewarded, that for which one is punished, and that for which one is neither rewarded nor punished. Whoever abandons a sin for the sake of Allah, while having the ability to commit it, is rewarded. Whoever abandons it for other than Allah is punished, because this abandonment is an act of the heart by which other than Allah was worshipped. As for one whose heart was not affected by knowledge, love, or hatred, their abandonment is like that of a sleeping person or a child.

A person is not punished for abandoning a sin out of shyness before people or fear of them. Rather, they are punished for seeking nearness to them and showing off to them through this abandonment, portraying themselves as someone who abandoned it out of fear and mindfulness of Allah, while the reality is otherwise. The difference is between abandoning an act to seek closeness to them (people) and abandoning it due to shyness or fear of harm. The latter is not punished, and may even be rewarded if it serves a purpose Allah loves, such as preserving the integrity of da'wah (inviting to Islam).