Here's the meditation for Ash Wednesday from the second book:

Meditation I - Especially for Ash-Wednesday

On Exterior Penance and Mortification

1st Point. There is nothing more united and less united than the soul and body. When one advances, the other recoils; when one rises, the other descends; when one is in health, the other is sick; when one is strong, the other is weak. It is necessary, then, in order to strengthen and give health to the soul, to bring the body under subjection, and weaken its evil propensities by penance and mortification.

I am not a man if I obey my passions; I am not a Christian if I do not combat with and overcome my passions; I am not a true penitent if I do not mortify my passions. Since my body is polluted by sin, it ought to be purified by pain; and since it has part in the pleasures of the soul, it ought to glory in sharing its sorrows.

2nd Point. How do I know that my sins are forgiven? How do I know that the pain which my offences merit is remitted? How do I know that God will not punish me in my body? How do I know that he will not chastise me in my soul? How do I know that he will not regard me with coldness, and permit me to fall into some grievous sin? How do I know that I shall be able to rise after falling therein?

3rd Point. If I spare myself, God will not spare me; if I love myself, God will not love me; if I hate myself, God will not hate me; if I punish myself, God will not punish me; if I excuse nothing in myself, God will pardon all; if I excuse all things in myself, God will pardon nothing; if I am indulgent to myself, God will be severe; if I am austere and harsh with myself, God will be merciful.

Oh, Christian soul! make your body a living and dying victim; mortify your passions, your senses, and your desires; mortify yourself at all times, and in all places; mortify yourself with zeal, mortify yourself with discretion.