Not advising strangers about sin

Walekumussalam,

A Hadees says that the Prophet ﷺ said:

“Whoever among you sees an evil, he should stop it with his hand. If he cannot, then with his tongue. And if he cannot do that, then he should at least consider it wrong in his heart, and that is the weakest level of faith.”

In light of this Hadees, if a person sees others doing a sin but feels shy or hesitant to advise everyone verbally, he will not be sinful, as long as he considers that sin wrong in his heart and does not approve of it.

However, if there is a suitable opportunity, it is better and rewarding to advise them politely and with wisdom.