We have a natural curiosity to find out what others are up to, but it is part our faith to leave this alone.
There is a story about the Prophet Musa (as). During a drought, he went out to the desert with 70,000 people and supplicated for rain. Nothing happened. Musa was expecting the supplication to be answered, and then Allah (swt) revealed to him that among them is a person who has been challenging Allah with sins for the past 40 years, and to call out on that person to repent because the rain is withheld due to him. So Musa called out to the people for this sinner to repent.
The sinner looked around and saw no one coming forward, and he realized this was about him. He did not want to go forward and expose himself. So he put his head down and said, “My Lord I have disobeyed You for 40 years and You have always given me respite. I come to you in obedience so accept it from me.”
He had barely finished this supplication when a cloud appeared overhead and rain started pouring down.
Musa then called out to Allah confused – no one came forward, yet the rain was sent down. Allah (swt) told him, “O Musa, I did not expose him when he was disobeying Me, then do you expect Me to expose him while he is obedient to Me?”