A Voice from the Past - Gregory the Great

But for the most part those who covet pastoral authority mentally propose to themselves some good works besides, and though desiring it with a motive of pride, still muse how they will effect great things: and so it comes to pass that the motive suppressed in the depth of the heart is one thing, another what the surface of thought presents to the muser's mind. For the mind itself lies to itself about itself, and feigns with respect to good work to love what it does not love, and with respect to the world's glory not to love what it does love. Eager for domination, it become timid with regard to it while in pursuit, audacious after attainment.

Gregory the Great,. 540-604 AD, Pastoral Rule, Part I, Chapter IX (translated by Rev James Barmby, Nicene and Post-Nicene Fathers, Philip Schaff and Henry Wace, T & T Clark and Wm. B. Eerdmans Publishers, 1997, Second Series, Vol. XII, p. 6)

Is it easy to fool ourselves about our own motives? How do we avoid this?