We must beware of the Past, mustn't we? I mean that any fixing of the mind on old evils beyond what is absolutely necessary for repenting our own sins and forgiving those of others is certainly useless and usually bad for us. Notice in Dante that the lost souls are entirely concerned with their past! Not so the saved.
C. S. Lewis (2014). “Letters to an American Lady”, p.103, Wm. B. Eerdmans Publishing