Luke 9:47

But our Lord, Who knew how to save, seeing in the hearts of the disciples the thought that had risen up thereupon as it were a certain root of bitterness, plucks it up by the roots before it received growth. For when passions first begin in us, they are easily subdued; but having gained strength, they are with difficulty eradicated. Hence it follows, And Jesus perceiving the thought of their heart, &c. Let him who thinks Jesus to be mere man, know that he has erred; for the Word, although made flesh, remained God. For it is God alone Who is able to search into the heart and reins. But in taking a child, and placing it beside Him, He did it for the Apostles' sake and ours. For the disease of vain-glory feeds generally on those who have the preeminence among other men. But a child has a pure mind and unspotted heart, and abides in simplicity of thought; he courts not honours, nor knows the limits of each one's power, nor shuns seeming to be inferior to others, bearing no moroseness in his mind or heart. Such the Lord embraces and loves, and thinks them worthy to be near Him, as those who had chosen to taste of the things which are His; for He says, Learn of me, for I am meek and lowly of heart.