[redgolum]

The overall message I am getting is that marital sex is somehow "bad", although I would not quote you as saying that outright. I am confused.

About the time the speculation of the Immaculate Conception was being developed, sex of any sort was viewed as bad. Or at least not a good thing. Augustine himself said that sex, even between a man and wife, is at best a venal sin and possibly a mortal one (if you only lusted after the spouse). There were a lot of reasons for this, much of it has to do with the influence of Plato's philosphy.

[adiaireton8]

That is a very uncharitable and misleading distortion of Augustine's position, who believed that marriage and sex in marriage were goods created by God. He affirmed that unrestrained or disordered sexual desire is wrong, but not ordered and properly directed sexual desire. Read again his treatise De bono conjugali ("On the Good of Marriage").

The person who chooses the life of consecrated celibacy over the life of marriage, has indeed chosen the better part. But that does not make marriage or the marital act sinful. As St. Paul says, "If you have married, you have not sinned, and if a virgin marries, she does not sin." (1 Cor 7:28)

-A8

[annalex]

About the time the speculation of the Immaculate Conception was being developed, sex of any sort was viewed as bad

Any evidence marital was viewed as bad by the Catholics? What you describe is a Puritan and a Gnostic belief, and St. Paul taught against it:

doctrines of devils, speaking lies in hypocrisy, and having their conscience seared, forbidding to marry ... (1 Tim. 4:2f)