Singleness of purpose.

     Devotion signifies a life given, or devoted, to God. He, therefore, is the devout man, who lives no longer to his own will, or the way and spirit of the world, but to the sole will of God, who considers God in everything, who serves God in everything, who makes all the parts of his common life parts of piety, by doing everything in the Name of God, and under such rules as are conformable to His glory.
Booth, William ; Wesley, John ; Bonar, Horatius; Ryle, J. C. ; Brengle, Samuel; Taylor, Jeremy; Law, William (2012-02-27). Top 7 Classics on Holiness: Purity of Heart, Heart Talks on Holiness, Holiness, God's Way of Holiness, Christian Perfection, Serious Call, Holy Living (Kindle Locations 11478-11480).  . Kindle Edition.

     This seems like a lofty ideal, unreachable by most Christians. Indeed we fall far short of this in the Church today. Yet this was normal Christianity for the early Church, This is the standard set forth in the new testament. Whatever we do in word or deed, we are to do in His name, and for His glory. This covers every aspect of life. Eating, drinking, working and resting, our thoughts, our plans all fall under this rule.
     It all comes down to our level of commitment to Christ, and the depth of our love for Him. He desires us to love Him with the totality of our being. We are to be consumed by our love for Him. Everything we do flows from love, with His glory as its motive. It is indeed a lofty place, a high calling, that can only be fueled by the fire of the Holy Spirit consuming the sacrifice of our lives. We must die to self, our plans, our wills, and let Him be all.