This is similar to what I tell my children.
"If it will bring you shame if people know about it, that's your first clue that you shouldn't do it."
"If you are trying to hide your behavior, that's a clue you are sinning."
"If you are keeping secrets, ask yourself why. Good surprises, like for birthdays, are OK, but hiding truth and bad behavior is not."
"If you have to lie about it, then you know you aren't doing right."
Christians should have no fear of their actions being exposed if they are living according to God's Word. In fact, we should want to live reasonably open lives to be a witness to others and to keep ourselves accountable.
Selfish motives will lead us to do the wrong thing, but God's Word does not.
Hebrews 4:12 For the word of God is alive and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart.