Can you keep a secret?
(Ps 44:21, 90:8; Lk 8:17; Rom 14:12; Heb 4:13). Jesus said, “There is nothing hidden that will not be made known…What you have whispered in the ear in the inner rooms will be proclaimed from the housetops” (Lk 12:2,3). We need to keep a close watch on our tongues so we don’t let slip what has been shared with us in confidence. Do not break trust by divulging what is shared with you in strict privacy. Counseling is undertaken on the condition that what is private will stay private. “A man of understanding holds his tongue. A gossip betrays a confidence, but a trustworthy man keeps a secret” (Prov 11:12,13). However, discretion must be used as some information can't be kept confidential, such as a person's threats to others or intentions to self-harm, acts of child abuse or major crime.
There is a right time and setting for confessing our sin (not that of others). Firstly this must always be in private to God, "He who conceals his sin does not prosper, but whoever confesses and renounces them finds mercy" (Prov 28:13; 1 Pet 2:16; 1 Jn 1:9). Then it may be right to do so before our fellow believers who can pray and support us, "Confess your sins to each other and pray for each other so that you may be healed" (Jas 5:16). Some aspects of our lives are best dealt with only between God and us.
We are not to keep our Christian life a secret, but live out our faith and speak about our relationship with the Lord as appropriate, "telling what great things the Lord has done for you" (Mt 5:14-16; Mk 5:19). Jesus said we are not to draw attention to our spirituality by publicising our "acts of righteousness", praying in public and fasting. While are to engage in these spiritual disciplines, it must be with the right motives of doing it as unto the Lord and not letting our left hand know what our right hand is doing (Mt 6:1-18, 25:40; Col 3:23).
Samson failed to keep the reason for his immense strength confidential, but under pressure from his wife divulged this and she told his enemies who took advantage of him (Jdg 16:16-21).