Fruitfulness/fecundity is a gift from God.
The two ends of the marriage act (marital intercourse) are the unitive end, i.e. bonding, and the procreative end (openness to life). The marriage act is never to dissociate these two ends.
This obviously does not mean that the marriage act will always result in the conception of a child.
It does mean that when a couple engages in the marriage act they are to be open through the language of the body to the possibility of a child being conceived.
When a married man and woman who are in sanctifying grace (the grace that makes us holy and pleasing in God’s eyes) engages in the marriage act, and when that act is open to life and love, God pours into the souls of the couple an increase of sanctifying grace!
Procreation is an end, an essential purpose of marriage and of the marital embrace.
Conjugal love naturally tends to be fruitful.
Children are not “add-ons” to the love of spouses, but are a result of the self-giving love the married couples are to show for one another.
Because it is God’s law, not merely man’s law, the Church, which is “on the side of life, teaches that it is necessary that each and every marriage act remain ordered, per se to the procreation of human life.” (CCC 2366).
When a couple contracept or is sterilized, they hold back a part of themselves from their spouse. It is impossible in this situation for a spouse to fully give him/herself one to the other. It is like saying, “I give myself to you, but not really, not totally.” Then the marriage act becomes a lie through the language of the body.
Human beings are not pure spirits like angels, but rather a body/soul unity. Both body and soul are good and important. What one does with his/her body has a profound effect on the state of his/her soul.
All this, then, rules out the legitimacy of contraception of any kind and direct sterilization, e.g. vasectomies and tubal ligations, both of which are gravely and intrinsically (by its very nature) evil, cf. CCC 2370.
If a person has contracepted or been sterilized, it is important that he/she repent of these sincerely and, if Catholic, confess these sins in the Sacrament of Penance (because they are sins of great gravity).
If we are sorry for our sins, confess them forthrightly to the Priest (who has authority given him by Christ to forgive sins in His name, cf. Jn. 20:19-23), and have a firm purpose of amendment, God will lavish His Divine Mercy upon us. “This is good and pleasing to God our Savior, who wills everyone to be saved and to come to the knowledge of the truth.” (1 Timothy 2:3-4)
When married couples conceive a child, they “share in the creative power and fatherhood of God.” (CCC 2367)
For just reasons, spouses may wish, by natural methods, to space the births of children. It is their duty to make certain that their desire is not motivated by selfishness but is in conformity with the generosity appropriate to responsible parenthood.
“Periodic continence, that is, the methods of birth regulation based on self-observation and the use of infertile periods, is in conformity with the objective criteria of morality.” (CCC 2370) These methods are referred to as Natural Family Planning. Natural Family Planning differs essentially from contraception.
By James Gontis, Director of Religious Education