CHAPTER I. The Necessity of Prayer.
1. 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.
2. 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. His Life has been meditated and written about by various authors. I should specially commend to you the writings of S. Bonaventura, Bellintani, Bruno, Capilla, Grenada and Da Ponte. 
3. Give an hour every day to meditation before dinner;—if you can, let it be early in the morning, when your mind will be less cumbered, and fresh after the night’s rest. Do not spend more than an hour thus, unless specially advised to do so by your spiritual father.
4. If you can make your meditation quietly in church, it will be well, and no one, father or mother, husband or wife, can object to an hour spent there, and very probably you could not secure a time so free from interruption at home.
5. Begin all prayer, whether mental or vocal, by an act of the Presence of God. If you observe this rule strictly, you will soon see how useful it is.
6. It may help you to say the Creed, Lord’s Prayer, etc., in Latin, but you should also study them diligently in your own language, so as thoroughly to gather up the meaning of these holy words, which must be used fixing your thoughts steadily on their purport, not striving to say many words so much as seeking to say a few with your whole heart. One Our Father said devoutly is worth more than many prayers hurried over.
7. The Rosary is a useful devotion when rightly used, and there are various little books to teach this. It is well, too, to say pious Litanies, and the other vocal prayers appointed for the Hours and found in Manuals of devotion,—but if you have a gift for mental prayer, let that always take the chief place, so that if, having made that, you are hindered by business or any other cause from saying your wonted vocal prayers, do not be disturbed, but rest satisfied with saying the Lord’s Prayer, the Angelic Salutation, and the Creed after your meditation.
8. If, while saying vocal prayers, your heart feels drawn to mental prayer, do not resist it, but calmly let your mind fall into that channel, without troubling because you have not finished your appointed vocal prayers. The mental prayer you have substituted for them is more acceptable to God, and more profitable to your soul. I should make an exception of the Church’s Offices, if you are bound to say those by your vocation—in such a case these are your duty.
9. If it should happen that your morning goes by without the usual meditation, either owing to a pressure of business, or from any other cause, (which interruptions you should try to prevent as far as possible,) try to repair the loss in the afternoon, but not immediately after a meal, or you will perhaps be drowsy, which is bad both for your meditation and your health. But if you are unable all day to make up for the omission, you must remedy it as far as may be by ejaculatory prayer, and by reading some spiritual book, together with an act of penitence for the neglect, together with a stedfast resolution to do better the next day.
[From 'Introduction to the Devout Life, Part Two, by St. Francis de Sales. Public Domain.]