"People who conceal their sins will not prosper, but if they confess and turn from them, they will receive mercy." (Proverbs 28:13 NLT)
King David tried to conceal his act of adultery and went so far as to murder the husband of Bathsheba, but eventually his sin was revealed. God used the prophet, Nathan to confront David with his sin. Fortunately, David was willing to repent and confess his sin, but the consequence was the death of his and Bathsheba's son.
It is never wise to conceal sin. Sweeping it under the rug will not remove the dirt or make the floor clean. No matter how great our sin, if we repent and confess it openly to God, he will forgive and cleanse our hearts. Keeping short accounts with God will result in freedom from worry and promote spiritual growth. 1 John 1:9)