Verbal Ability - Idioms and Phrases - Discussion

The thief decided to make a clean breast of and tell the truth near the King.

To eliminate the guilty feeling inside you, yo open the truth to eliminate that feeling i.e to feel better.

To tell the truth about something, especially something bad or illegal that you have done, so that you do not have to feel guilty any more.

To make a clean breast meaning - Admit or acknowledge a wrong doing.

An idiom has peculiar meaning that must be remember by perception.

Its mean to reveal the secret which is not known to any one.

The word "clean" means to make it pure, erase, wipe out so in the given option "To confess without of reserve" - the word confess means to come out with the truth and come clean of without being party to any crime or hidden incidents. Hence the word "clean" interacts with the word "confess".

Many a times we have heard a dialogue in Hollywood serials or movies. "He has come clean" means he has either confessed of his crimes without any pressure or he has confessed to the jury or the cops about being an accomplice.

To make clean breast of means open up the truth.

Can any one give better explanation?

Can any better explain?