The necessity of prayer

"Prayer opens the understanding to the brightness of Divine Light, and the will to the warmth of Heavenly Love—nothing can so effectually purify the mind from its many ignorances, or the will from its perverse affections. It is as a healing water which causes the roots of our good desires to send forth fresh shoots, which washes away the soul’s imperfections, and allays the thirst of passion.

But especially I commend earnest mental prayer to you, more particularly such as bears upon the Life and Passion of our Lord. If you contemplate Him frequently in meditation, your whole soul will be filled with Him, you will grow in His Likeness, and your actions will be moulded on His. He is the Light of the world; therefore in Him, by Him, and for Him we shall be enlightened and illuminated; He is the Tree of Life, beneath the shadow of which we must find rest;—He is the Living Fountain of Jacob’s well, wherein we may wash away every stain. Children learn to speak by hearing their mother talk, and stammering forth their childish sounds in imitation; and so if we cleave to the Savior in meditation, listening to His words, watching His actions and intentions, we shall learn in time, through His Grace, to speak, act and will like Himself. Believe me, my daughter, there is no way to God save through this door. Just as the glass of a mirror would give no reflection save for the metal behind it, so neither could we here below contemplate the Godhead, were it not united to the Sacred Humanity of our Saviour, Whose Life and Death are the best, sweetest and most profitable subjects that we can possibly select for meditation. It is not without meaning that the Saviour calls Himself the Bread come down from Heaven;—just as we eat bread with all manner of other food, so we need to meditate and feed upon our Dear Lord in every prayer and action."

-- Introduction to the Devout Life by St Francis de Sales