NFP is great, We used it ourselves for several years. But I have to go with Cynic reguarding the morality of it. If God wants you to have kids, and you avoid having relations when it would be possible for you to have kids, it is the same as using a barrier contraceptive. I mean if God wanting or needing you to bring souls to earth is the argument for morality or immorality. Either way, you are just as certainly thwarting God’s wishes. If, as is claimed here, NFP is more effective than most contraceptives, then you are thwarting God’s wishes even more effectively!
It is not the worthiness of NFP that is being argued, it is the ideas being used to support it.
I understand the slippery slope arguments etc. I agree that NFP has much to merit it, and I think it is fine for the church to teach it. But the arguments for why it is OK, and other barrier methods are immoral don’t hold water.
If God wanted or needed our co operation to bring souls to the world, then any effort to thwart that would be equally immoral.
If God is capable of having us conceive even when using NFP correctly, then God is capable of having us conceive through a failure of barrier method as well.
I am not arguing NFP, I am arguing your argument.
cheddar