The temp with wind-chill was around 20 below zero, and my beard literally had icicles hanging from it from my exhale and my hands were freezing. I kept praying, asking the Lord to intervene and give me His strength to continue, if in fact He had called me to run this marathon - which, deep down, I knew He had.
This being the 3rd full day of my fast and around 1:30 am after having already run about 7 miles or so, I had reached a point of such a feeling of utter emptiness, fatigue, and weakness that I knew that if I answered my body's inclination, I would simply have to stop running and walk home if possible, or worse, just call my wife to come pick me up.
I had come to the end of my own natural strength and knew that I would have to rely entirely on the Lord's grace to empower me to finish. This "ending" of our own strength is of course partially figurative in the sense that I still ultimately had some strength left, but it is the reliance on the Lord for His sustinence that constiutes the actual exchange of strength that I'm referencing. It is in this blurring of the lines between our own strength and His that our trust and self-confidence is transferred from ourselves in our own natural abilities or talents or "strengths", to a total reliance on God's sustaining power.
That night, was the first night that I exceeded 13.1 miles. (I'll edit this post to include the actual mileage when I can locate my journal entry from that day.)
At some point ( I remember the section of road) I suddenly felt strenth returning to my legs and my breathing came easier. I transitioned from my "trudging", shuffeling type pace to an easy jog and within a short distance was able run at my normal pace...
From that night forward, I knew the Lord was with me in this and I was now confident that I'd be able to finish the marathon.