"He that raised up Christ from the dead shall also guicken your mortal bodies by His Spirit that dwelleth in you" (Romans 8:11)
Our Lord is able to work with a minimum of weariness because He was a man completely possessed by the Holy Spirit. As a man He did not grow tired and had to sleep and rest and refresh Himself, but the strain and the exhaustion that He would otherwise have suffered were spared Him by the constant quickening of the Holy Spirit.
Peter explained that Christ "went about doing good, and healing all there were oppressed of the devil," after God had "anointed [Him] with the Holy Spirit and with power" (Acts 10:38).
It is possible to work far beyond the normal strength of the human constitution and yet experience little or no fatigue because the energy for the work has been provided, not by the burning up of human tissue, but by he indwelling Spirit of power. This has been realized by a few unusual souls, and the pity is that they are "unusual."
To live in the Spirit is to receive the life of the Holy Spirit in our physical being and to find in Him the source of constant stimulus and strength for our mind and all the functions of our body.
~A. W. Tozer~