Excuse me for barging in, but it might be time for more people to intrude into the marital bedroom. Though there are some good Christian books on marital sex, most of them repeat two basic mantras: (1) Christians are not sexually reserved. Behind closed doors we are incredibly frisky and uninhibited, and (2) let your conscience be your guide. If a particular form of sexual expression is acceptable to both spouses, it is okay with God. Let’s not get legalistic in matters where we have freedom of conscience.

I’m not so sure about either of these.

On point number one, maybe we are really frisky, maybe not. It is more likely that we are similar to most married people—sometimes we are sexually motivated, sometimes we would rather take a nap.

On point number two, a conscience, when it comes to sex, can get seared very quickly, so maybe conscience alone cannot be your guide. Better to take the Apostle Paul’s admonition. “Whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things” (Phil. 4:8).

Years ago I became aware of a pastoral situation involving a married couple. While another elder and I were trying to understand what was happening, someone quietly informed us that the husband and wife occasionally indulged in bondage scenarios. Our response? Nothing. We might have asked a follow-up question, but, if we did, the couple made it clear that the bedroom was their domain, and we had no right intruding. So we didn’t. We obeyed law number two and it was probably a mistake. Two years later the husband was outed for extramarital sexuality.

God cares about our sexual imaginations, even married ones. The limits of what is okay to imagine (or do) is not up to our discretion. Yes, a godly sexual imagination can drift off to a tryst in an edenic secret garden, but it should never drift off to a person other than your spouse or to anything that approaches bondage, power or pain scenarios.

The godly sexual imagination is fundamentally animated by the most sensual principle of all: “I am my beloved’s and my beloved is mine” (Song of Solomon 6:3).

Exclusivity. Sex is something we share with each other and no one else. I belong to you alone. You belong to me alone. This should be enough to fuel the most anemic imagination.

Christian bedrooms, I suspect, are doing less well than we think. Friskiness, when it exists, too often relies on illicit imaginations. Our consciences can be sexually reckless. So we aim for a sanctified sexual imagination, which means we are not aiming for the sexuality that we see in our culture. Instead, we find pleasure in exclusivity and openness.