Chapter 58 — The number of the sacraments of the New Law
Since, as stated above, (Ch. 56.) the remedies of spiritual welfare have been given to man under sensible signs, it follows that the remedies which give life to the soul differ from one another in a manner that corresponds with the life of the body.
In the life of the body, there is a twofold order. There are those who propagate and direct this life in others, and there are those who are propagated and directed to corporal life.
Three things are essentially necessary to the life of the body, and a fourth is required accidentally. In the first place, a thing needs to receive life by generation or nativity; second, it needs growth so as to attain to its proper size and strength; third, it needs nourishment for the preservation of the life thus generated and developed. These are essentially necessary to natural life, since without them the body cannot live: hence to the vegetative soul, which is the principle of life, are assigned the three natural forces of generation, growth, and nutrition. Since, however, the life of the body meets with obstacles, which cause the body to ail, a fourth thing is necessary accidentally; this is that the living being be healed of its ailments.
Accordingly, in the spiritual life there is first spiritual regeneration by baptism; second, spiritual growth by confirmation, bringing the soul to perfect strength; third, spiritual nourishment by the sacrament of the Eucharist; and fourth, spiritual healing, which is given either to the soul only by the sacrament of penance, or, when it is expedient, to the body through the soul by the sacrament of extreme unction. These concern those who are propagated and safeguarded in the life of the soul.
The propagators and directors of the life of the body are required from two points of view, namely, in respect of natural origin, which concerns the parents, and in respect of political order (whereby man is assured a peaceful life), and this regards kings and governors.
Thus is it also in the life of the soul. There are those who propagate and safeguard the spiritual life by a purely spiritual administration: to these corresponds the sacrament of orders. And there are those who propagate and safeguard the spiritual life by ministering to both body and soul: this is the object of the sacrament of matrimony, in which husband and wife are joined together in order to beget children, and bring them up in the fear of God.
Chapter 424 of 463