"To open the chest" means to reveal or access something hidden or secret, typically referring to emotions, thoughts, or information that were previously concealed.
Sentences with «to open the chest»
Players can collect coins as they defeat enemies or open chests in the environment. (adweek.com)
I like to gently turn my palms forward to open the chest for breathing. (vikasayoga.com)
Learn how far your desires can go and open a chest of naughty wonders. (petesgrillandpizza.com)