Volumes have been written on the views of the early Christian church on sex and marriage.  This will serve as a quick introduction to the layman.  The notes provide references  for anyone interested in deeper study of the topic.

The early church was influenced by the Greek philosophy of Plato and others who advocated the philosophy of dualism. Dualists believed that the physical world is evil, and only by escape from the physical into the spiritual can there be salvation. Physical pleasure was to be shunned – hence the ascetic lifestyle of these philosophers and their followers. As a result, sex and the necessary framework of marriage in which it occurs has traditionally been viewed by Christians as a necessary evil. Augustine was Manichean, a religion that taught dualism, before converting to Christianity.

Augustine acknowledged that the command in Genesis to be fruitful and multiply necessitated sex, and sex per se was not sinful. However, he taught that sex in its current form is not what God originally intended. “When [in Eden] those parts of the body were not impelled by turbulent ardor but brought into play by voluntary exercise as the need [for children] arose, and the male seed could be introduced into the wife's uterus without damage to the maidenhead, even as now the menstrual flow can issue from a maiden's uterus without any such damage.” note

Early Church fathers held that the act of intercourse propagates original sin. Augustine used Psalms 51:5 (Behold, I was brought forth in iniquity, And in sin my mother conceived me. note) All scriptural quotes are from the New King James Version unless otherwise noted. to support his belief that the pleasure resulting from the act of generation propagated the original sin. note Augustine, Exposition on Pslam 50. Look for Psalm 50:5 in item 10. The chapter and verse numbering is different in Protestant and Catholic Bibles. While Augustine described sex for the purpose of procreation as guilt-free,  Pope Leo the Great taught that all intercourse is a sin. note Eunuchs for the Kingdom of Heaven, p. 136, 141-142.

The Roman Catholic and Eastern Orthodox Church as well as Lutherans and Anglicans hold that Mary was a virgin, not only when she conceived Jesus from the holy spirit, but she remained a virgin the rest of her life. note Perpetual Virginity of Mary, Wikipedia  Her hymen was said to have remained intact in spite of childbirth. Jesus’ brothers and sisters first became step-sisters from a previous marriage of Joseph, then cousins. It would not do to have the earthly father of our Savior tainted by lust. note Eunuchs for the Kingdom of Heaven, p. 31 This teaching ignores Matthew 1:25 which tells us that Joseph “knew her not till she had brought forth her firstborn son: and he called his name JESUS.”

Sex was not permitted on Sundays, all of the feast days, or in the days preceding Easter, Christmas, Pentecost, or taking communion, for a total of about 40% of the year. note

Eunuchs for the Kingdom of Heaven, p. 138

To it’s credit, the Catholic church now acknowledges the unitive value of sex in marriage. In 1977 cannon law was changed to permit marriage by men who are sterile. note

Eunuchs for the Kingdom of Heaven, p. 77

This in in stark contrast to Judaism. Sex is not only permissible on the Sabbath, but considered a special blessing when partaken of on that day. Sex for reasons other than reproduction is recognized as legitimate. All major modern sects of Judaism permit birth control. There is a long tradition of using sterilizing potions and other methods of birth control during famines.ii While the Jewish society is patriarchal, women are and were highly esteemed, loved, protected, and appreciated. Jews never performed clitorectomies as was common among other Semitic peoples. Married men were given a year's exemption from military duty "to give happiness to the woman he has married" (Deuteronomy 24:5). The Song of Solomon is recognized as erotic.

The Sabbath, a time of joy in the Jewish community, is personified in Jewish tradition as a bride whose bridegroom is Israel. The song Lechah Dodi (לכה דודי‎‎ Come, my love), written in the early 16th century by Solomon Alkabetz, begins "Come, my love, to greet the Sabbath Bride." This song has become an integral part of the Friday-night liturgy used by Jews today. The plural of the word dod (דוד lover, Strong's 1730), is dodim (דֹ֭דִים), which also means "sexual intercourse." (See Ezekiel 23:17) The sexual connotation is clear. Indeed, weddings in the middle east are often conducted on Friday evening, the evening before the Sabbath. note

Theodor H. Gaster, Festivals of the Jewish Year, Morrow, New York, 1978, p. 282.