Soren Kierkegaard famously said, “purity of heart is to will one thing.” 
To center back on our call to will one thing, namely the will of God, is the chief purpose of Lent. This week’s gospel reading comes from Matthew 4:1-11. It’s the scene of Jesus’ temptation in the wilderness. The Liar and Destroyer tempts Jesus, beckoning him to use God’s power to turn stones to bread, to use God’s power to call the angels to his aid, and he offers him the authority over all the kingdoms of the world, if only Jesus would will to bow down to the Deceiver.
But Jesus does not. Â He wills only one thing–only that which the Father wills. He is pure in heart.
And the Father does not will that his power be displayed in turning rocks into food or in swarms of angels coming to his Son’s aid, or in worldly rulership over the civilizations. His power will be displayed on the cross. Jesus will display the will of the Father in dying, giving himself up for the adulterous idolaters (see Hosea) in order to offer them the life and the love for which he created them.
To will one thing is pure. What is that one thing for us–for those of us on this side of the historical cross?
“Father in Heaven! What is a man without Thee! What is all that he knows, vast accumulation though it be, but a chipped fragment if he does not know Thee! What is all his striving, could it even encompass the world, but a half-finished work if he does not know Thee: Thee the One, who art one thing and who art all! So may Thou give to the intellect, wisdom to comprehend that one thing; to the heart, sincerity to receive this understanding; to the will, purity that wills only one thing. In prosperity may Thou grant perseverance to will one thing; amid distractions, collectedness to will one thing; in suffering, patience to will one thing. Oh, Thou that giveth both the beginning and the completion, may Thou early, at the dawn of day, give to the young man the resolution to will one thing.” — Kierkegaard, Purity of Heart is to Will One Thing
About the author:
My wife and I live in South Hamilton, MA where I'm pursuing an MDiv at Gordon Conwell Theological Seminary and she's serving as Intervarsity staff on campus at Northeastern University. I study Theology and History and Philosophy "as ends in themselves" (in the Aristotelian sense), as well as for a further, more complete end: a deeper understanding of my King and, thus, a more dynamic relationship with him.
I graduated this past spring (2013) with BA in Religious Studies (Hinduism and Buddhism concentration) and a minor in Classical Greek (Homeric/Ionic/Attic/Doric/Koine, appx. 8th BCE - 5th CE). The study of the ancient world in its original context and language fascinates me, especially that of the Early Christians, Ancient Jews and Hellenes.
For more of my writing, see my blog @ www.philotheology.com