Christian Living

What Is Sexual Immorality?

Live a Life of Purity and Avoid Being Sexually Immoral

In studying Revelation for my book, A New Heaven and a New Earth, two recurring phrases are sexual immorality and sexually immoral. The Bible decries this is something to avoid. But that begs the question: what is sexual immorality?

No Moral Absolutes?

The world teaches us that there are no moral absolutes. It asserts that it’s up to each person to determine what is morally right for them. This sounds nice. It’s accommodating, but remember in Judges when everyone did what was right in their own eyes? That is, everyone did as they saw fit (Judges 17:6).

This attitude of each person choosing their own moral path separated them from God, and they fell victim to a series of oppressors as a result. We can’t define what morality means at an individual level and expect our determination to please God.

Since it’s not going to work to decide for ourselves what it means to be sexually immoral, let’s look at what the Bible has to say.

Sexual Immorality in the Old Testament

Though we might assume this is an Old Testament concept, warnings about sexual immorality occur mostly in the New Testament.

There is one lone verse in the Old Testament about sexual immorality. You may guess it’s in reference to Sodom and Gomorrah, but it’s not. Ezekiel says that Sodom’s sin was their failure to help the poor and needy, Ezekiel 16:49. He doesn’t mention their sexual practices.

The one Old Testament reference to sexual immorality occurs when the men of Israel engage in sexual immorality with Moabite women, who use sex to entice the men to worshipping their gods instead of the true God. The Lord Almighty is not pleased (Numbers 25:1-3).

This doesn’t mean that the Old Testament is silent on the concept of sexual purity. The law of Moses repeatedly lists—with squirm-producing unease—the relatives who people can’t have sexual relationships with (Leviticus 18:6-23).

I’d have been much more comfortable with Moses simply saying to not have sex with a close relative and left it at that.

Sexual Immorality in the New Testament

In the New Testament, Jesus warns against sexual immorality, Luke covers it in the Book of Acts, and Paul writes about it to the various churches—especially the Corinthians.

And John’s epic end-time vision addresses sexual immorality too, making it abundantly clear that it’s something we should avoid.

What Does the Bible Teach?

In the NIV, Scripture prohibits adultery (sex between a married person and someone other than their spouse), mentioning it forty-five times.

The Bible decries prostitution (sex for money or personal gain), mentioning it thirty-six times, with prostitute showing up seventy-four more times.

Rape (forced or nonconsensual sex) appears nine times.

The evils of incest (sex between closely related relatives) is directly mentioned once, but the concept shows up repeatedly.

Though not mentioned in the NIV, the KJV speaks against fornication (sex between unmarried people) thirty-five times.

Lest there be any doubt, these two hundred various mentions of sexual conduct never occur in a positive manner in Scripture. We can, therefore, use these biblical passages to show us what it means to be sexually immoral.

It’s clear from all these verses that sexual immorality is sex outside of marriage.

If our determination of sexuality doesn’t align with what the Bible teaches, then we’re out of step with what the Word of God proclaims and what God desires for us.

Even if society applauds us for doing so, God does not. In the end, it’s God’s opinion that matters, not the world’s.

What About Matters of Conscience?

The Bible makes it clear about what sexual behavior is acceptable and what is unacceptable. Paul, however, does make an allowance for conscience, but it may not be what you think.

Paul allows believers to pursue an even higher standard. Abstinence. Paul models this and recommends it as an ideal, but he doesn’t command it. He makes sure we realize it’s optional (1 Corinthians 7:1-7).

Given All This, What Is Sexual Immorality?

In the delusion of an anything-goes worldly mentality, as followers of Jesus we should adhere to the biblical teaching that sexual immorality is sex outside of marriage.

[Read through the Bible with us this year. Today’s reading is Numbers 25-27 and today’s post is on Numbers 25:1-3.]

Peter DeHaan writes about biblical Christianity to confront status quo religion and live a life that matters. He seeks a fresh approach to following Jesus through the lens of Scripture, without the baggage of made-up traditions and meaningless practices.

Read more in his books, blog, and weekly email updates.

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