12 Come then, Brother, be reformed. You are afraid lest your enemy should prosecute you; and are you not afraid lest God should judge you? Where is your faith? Fear while there is the time for fear. Far off indeed is the day of judgment; but every man's last day cannot be far off; for life is short. And since this shortness is ever uncertain, you know not when your last day may be. Reform yourself today, because of tomorrow. Let the reproof in secret be of service to you now. For I am speaking openly, yet do I reprove in secret. I knock at the ears of all; but I accost the consciences of some. If I were to say, “Thou adulterer, reform yourself;” perhaps in the first place I might say what I had no knowledge of; perhaps suspect on a rash hearsay report. I do not then say, “Thou adulterer, reform yourself;” but “whosoever you are among this people who art an adulterer, reform yourself.” So the reproof is public; the reformation secret. This I know, that whoso fears, will reform himself.
Source: Sermons on Selected Lessons of the New Testament (New Advent)