In the Bible 1st John 1:9 says, "If we confess our sins, He is faithful and righteous to forgive our sins and to cleanse us from all unrighteousness."
Privately naming all known sins to God fills you with the Holy Spirit and puts you back in fellowship with God, the same state Jesus Christ was in for his entire life until God sacrificed him on the cross to be judged for all sin past, present, and future, for the entire human race. Being in fellowship with God through private confession is the key to learning God's plan for our lives. That is why John 4:24 says, "God is spirit, and those who worship Him must worship in spirit and truth." Being in fellowship is also the only way the Holy Spirit can guide you to becoming spiritually mature.