A friend said it doesn’t make sense for the Church to permit Natural Family Planning (NFP) while banning artificial means such as the pill. Aren’t these just two different ways of contracepting?

The mere fact that artificial contraception and NFP have the same end in view, avoiding pregnancy, doesn’t mean they’re morally equivalent. There’s nothing wrong with avoiding pregnancy, per se, under certain circumstances. It’s the means used to do so which are of concern here.

For example, you can support your family by honest work and diligence or you can rob banks to do it. The end is the same in both instances, but that doesn’t mean the means used are morally equivalent. Honest labor is moral. Theft isn’t.

NFP isn’t contraception. In contraception an action is taken which prevents conception. In NFP, no such action occurs. Instead, sexual relations are avoided when conception is likely to occur.

Contraception violates the natural link between the procreative and unitive aspects of the marital act. This link, as Humanae Vitae teaches, is established by God and may not be broken by man on his own initiative (HV 12). NFP doesn’t alter the marital act in any way.

Is it possible to misuse NFP? Yes. It can be used to exclude children from marriage altogether, and that is counter to one of the purposes of marriage. It can be used to exclude children for selfish, unchristian reasons. In such instances, the purpose for avoiding pregnancy is disordered, but not the means (NFP).