The primary thief of joy and peace is regret. Whether it is something that you did today or yesterday, or many years ago, there is nothing that you can do about what has already been done– except repent, receive forgiveness, forget the past (at least don’t be control by it) and move on.  Now by all means, if it is something that you can do about it, then do it!  But the bottom line is to let go of the past and focus on the present.  Make a decision today to no longer live a life of regret (Philippians 3:13).