no sin, however secret...

David O. McKay: No man can disobey the word of God and not suffer for so doing. No sin, however secret, can escape retribution. True, you may lie and not be detected; you may violate virtue without it being known by any who would scandalize you; yet you cannot escape the judgment that follows such transgression. The lie is lodged in the recesses of your mind, an impairment of your character that will reflect sometime, somehow in your countenance or bearing. Your moral turpitude, though only you, your accomplice, and God may ever know it, will canker your soul.

(Book: "Gospel Ideals," p. 383)