WARNING: Be advised this post contains sexual content. Not meant to trigger anyone.
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I heard a lot of misunderstandings of Catholic morality (Natural Law, actually) on Jason Whitlock's podcast recently. I want to help clear things up.
HERE'S WHAT THE CATHOLIC CHURCH TEACHES ABOUT SEX:
Sex is meant for men and women in marriage (which is why it's called the "marital act").
Intentionally achieving climax with the hand, the beginning or end of one's digestive tract, or by any other means is wrong. It should happen in the context of "regular sex"; which is to say, the kind of union that is open to reproduction. Other forms of sexual releases are inappropriate substitutes; they are sinful.
Why?
REMEMBER THAT THE NATURAL EFFECTS OF SEX are twofold: bonding and babies (or love and life).
The obvious purpose of sex is reproduction, but not to the exclusion of the pleasurable bonding between man and wife.
The problem comes when doing the act while intentionally cutting out one of those two ends. That's why rape is wrong. That's why adultery is wrong. That's why porn is wrong. That's why homosexual acts and bestiality are wrong. And -- it's why contraception is wrong.
What about old or otherwise infertile people? It's not wrong for an infertile married couple to engage in sexual relations. Even the youngest, healthiest couples are fertile only for a few days a month, but that fact of nature doesn't make it wrong to act as man and wife throughout the month (it's how God made us). It is only wrong when they engage in sexual acts that by nature render conception impossible (or has that intent).
Married couples should have lots of sex and be generous with life. If for some very serious reason they desire to avoid conception, the couple can always agree upon periodic abstinence. It doesn't need to be six months at a time, or in perpetuity. With the help of science, the couple can practice "Natural Family Planning," which, if followed carefully, can be quite precise in letting you know when conception is not on the table. That's most of the month actually, so it's not like you're missing out that much. Close the door and have at it.
If it gets to be too difficult to wait during the fertile times, then you can talk and decide how "serious" this reason really is to avoid conception. Maybe you'll both change your mind.
But what's unacceptable is to perform sterile acts of selfish gratification on each other in order to avoid pregnancy and to get one's rocks off. That's not love, even if in the heat of the moment you wish it to be.
For any Protestants who say all this is not "biblical," they should provide us with "biblical" proof or positive examples of masturbation, oral/anal "sex," or barrier or withdrawal methods. I'll wait.
Even married couples are capable of sexual sin. There's no "anything goes" clause in marriage.
Before saying all this is too rigid, or unfair, or too hard -- remember that we indeed live in a hypersexualized society. When we think we "deserve" sexual release any time we want, any way we want, we need to rethink our priorities, our lives. It's not the Christian Church, but the world that says "gay marriage" is fine, chopping off our body parts is fine, bondage and whips and other weird, creepy sex stuff is fine.
We should live in a holy manner even when it's difficult. Trust God. He knows it's not easy. We have to put on the whole armor of God so we can stand in the evil day.
Love your spouse.