NFP: What's the Difference? by Sara Fox Peterson


peterson_saraImagine two hypothetical couples, each with the same number of children, the same financial and material resources, the same psychological stresses and health concerns, each with a serious, selfless reason not to conceive another child.

One couple uses NFP to avoid pregnancy.

The other uses contraception.

Neither conceives.

So what’s the difference?

Why is one (the couple using NFP to avoid pregnancy) cooperating with God’s call to responsible parenthood and the other (the couple contracepting) engaged in something gravely immoral?

Consider this analogy: Suppose that I have a serious and morally good reason to lose weight, but that there is a pint of double-super-chunk-fudge-brownie ice cream – with nuts and marshmallows – in my freezer and I have already eaten a full dinner.

Now I may really want to eat that ice cream and the pleasure derived from the act of eating ice cream is a God-given good and something it is perfectly reasonable for me to desire, but the consequences of that act (namely the 40 gazillion extra calories) would not be a good thing at this particular time.

I could eat the ice cream and at the same time attempt to interrupt the natural processes that lead from chewing to swallowing to digestion to the absorption of the calories that I ought to avoid and I could theoretically interrupt this process in a number of ways. I could chew the ice cream, but spit it into the sink instead of swallowing it. I could swallow the ice cream, but only after installing a physical barrier in my throat so that it would not reach my stomach to be digested. I could have myself hormonally or surgically altered so that I was no longer able to digest ice cream at all.

Or I could refrain from eating the ice cream and avoid the consequences in that way.

The result – the end – is the same in both cases, but clearly the means are not and the morality of any act is dependent on both the end and the means.

And a difference in the means – in the way in which pregnancy is avoided – is the critical difference between contraception and NFP. Some of the above ideas for avoiding the caloric consequences of ice cream eating may be somewhat distasteful. It’s unnatural and a little weird to think about altering either the act of eating or our bodies so that the normal process of digestion is impeded. But that a married couple would ever feel that the very act intended by God to be the physical sign of their marriage vows – the way in which those vows are supposed to take flesh in their marriage – should be altered so that its consequences could be avoided, is a great deal more than unnatural or weird. It is tragic.

Christian marriage is a sacrament and the sexual act is the physical sign of that sacrament in the same way that the body and blood of Christ under the appearance of bread and wine are the physical signs of the Eucharist. Consider for a moment how shocking it would be to see someone receive the Eucharist and then “undo” the consequences of the act by spitting out the host. Contraception should shock us no less.

And what about the other side of the coin – the objection that NFP is just as immoral as contraception because it does not allow God total control over the number and spacing of a couple’s children?

This is true up to a point. We are all called to be generous in our acceptance of children and married couples should feel free to enjoy sexual relations as often as they desire while being ready to joyfully welcome any children with whom God blesses them unless there is a serious reason not to.

Here too ice cream provides a good analogy. The act of eating ice cream in and of itself is morally good. Humans are designed to enjoy sweets – even newborn babies strongly prefer sweet tasting liquids and human breast milk is remarkably sweet. But there are times when the good of eating ice cream ought to be foregone for the sake of a greater good. If I am severely obese, have high cholesterol and have been warned repeatedly that I will almost certainly have a heart attack and be unable to care for my children if I do not modify my diet, to go ahead and eat as much ice cream as I desire whenever I desire is to fail to exercise the virtues of both prudence and temperance and is therefore morally wrong.

The fact that something is objectively good does not mean it is always right for us to partake of it. The Eucharist is wholly and unquestionably good. Yet there are times – when we have not fasted or are not in a state of grace – when it would actually be seriously wrong for us to receive it.

If a couple has discerned through prayer, reflection and discussion that they have a serious reason to avoid pregnancy and that it is not God’s will for them to conceive again at that time, then they are called to cooperate with God and periodically (during the fertile phase of the wife’s cycle) sacrifice something good that they rightly desire – sexual relations – for the greater good of each other or the children they already have.

After all, isn’t the willingness to give up something good and desirable for the sake of another one of the defining characteristics of Christian love?

Copyright 2009 Sarah Fox Peterson


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  1. Sara Fox Peterson on

    I’m not aware of any particular moral problem with lap-banding, etc. Eating and digestion are physical processes and, while one can engage in them in a way that is sinful (ie gluttony), there is no particular spiritual significance to the acts themselves.

    The ice cream analogy was just intended to illustrate how the same end could be accomplished through very different means and not to imply that all physical processes are sacred in the same way that sexual intercourse is.

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