I was once told Hebrews 13:4 meant anything goes in the marriage bed, but some interpret it to me 'don't do anything to defile the marriage bed. ' If you read it in context the latter interpretation also checks out. Right or wrong, some Christians are expressly told what they can and cannot do in the marriage bed.
Here's the full verse : [Let] marriage [be] had in honor among all, and [let] the bed [be] undefiled: for fornicators and adulterers God will judge.
It says that the marriage bed is undefiled. Its also saying not to commit adultery. Fornicators refers to the phallic cults common in the world at that time.
Many in the Roman culture treated casual sex as if they were simply eating food. Do you have any moral compunction when ordering a slice of pizza? The Greek culture that permeated the Roman world saw sex as just another normal physical function like eating food ... Having no more a moral attachment to it than going out to eat steak.
Promiscuity (what we would call it today) was an unquestioned norm to them. That is why some get confused about Paul's writings to the gentiles. Paul was not a prude. He did not hate sex. He was trying to reign in the amoral norms that gentile believers were accustomed to. They were accustomed to going to the pagan temples to have a good meal.. and maybe have sex with either a
male prostitute.. female prostitute... child prostitute.. and for some, even animals. The sex was seen as a religious obligation. The pagan temple sex is what the word
fornication meant to them back then.
It was a weird amoral world before God began moving in the gentile nations of the Roman Empire.
You say, “Food for the stomach and the stomach for food,
and God will destroy them both.” The body, however, is
not meant for sexual immorality but for the Lord, and the
Lord for the body." 1 Cor 6:13
Paul needed to write that because that was the attitude they held before they believed in Christ. Sex with any one they wished to them was like going to a McDonald's to get a hamburger. What we call infidelity today, to them was simply an accepted a way of life.
There divorce rate was very low because almost no one married for love. They married to keep their race going. Sex outside of marriage was their accepted life style. Rome was almost totally decadent.. and there comes along the Church to knock it on its rear!
Regeneration introduced these gentile believers to knowing love for the first time. That is why the NT speaks so much about love to the pagan world. The Holy Spirit was being transformational to the world. The indwelling Holy Spirit being spread with the Church as it was taking back from Satan God's creation of man.
God created man for love.