A believer should conceal what sins he may commit

English translation

Narrated Abu Huraira:

I heard Allah's Messenger (ﷺ) saying. "All the sins of my followers will be forgiven except those of the Mujahirin (those who commit a sin openly or disclose their sins to the people). An example of such disclosure is that a person commits a sin at night and though Allah screens it from the public, then he comes in the morning, and says, 'O so-and-so, I did such-and-such (evil) deed yesterday,' though he spent his night screened by his Lord (none knowing about his sin) and in the morning he removes Allah's screen from himself."

English translation

Narrated Safwan bin Muhriz:

A man asked Ibn `Umar, "What did you hear Allah's Messenger (ﷺ) saying regarding An-Najwa (secret talk between Allah and His believing worshipper on the Day of Judgment)?" He said, "(The Prophet (ﷺ) said), "One of you will come close to his Lord till He will shelter him in His screen and say: Did you commit such-and-such sin? He will say, 'Yes.' Then Allah will say: Did you commit such and such sin? He will say, 'Yes.' So Allah will make him confess (all his sins) and He will say, 'I screened them (your sins) for you in the world, and today I forgive them for you."'