St. John Chrysostom on sleeplessness

Almost all of us at times find ourselves unable to sleep at night.  We lie awake during the dark, silent hours. 

This rarely happens when our hearts and souls are at peace; it usually happens when we are troubled in some way.  For this reason do not curse your lack of sleep.  These times of wakefulness have been sent by God as a sign that something is wrong, and as a period for reflection.  So when you cannot sleep, allow the thoughts that lie deepest in your heart to rise up to the surface.  Often these thoughts are a reproach, telling you of a sin you have committed or an act of charity you failed to perform.  If you have already confessed and made amends for these past failures, then you must assure yourself that God has forgiven you, so that you can sleep in peace.  But if you have not confessed and made amends, then you must confess at once, admitting to God the precise nature of your sin, and asking forgiveness.  Then you must plan how the following day you can put right your wrong.  You might be so troubled that even then you cannot sleep.  But do not worry:  your mind and body will eventually sleep when your soul is at rest.