“Do not defile yourselves in any of these ways, because this is how the nations that I am going to drive out before you became defiled.” (v.24)
Notice that "do not defile" is not a suggestion, but a commandment. A commandment not to destroy our joy of life, but given that we might enjoy true life, as God intended it to be lived. The commands of chapter 18 weren't just “Old Testament only” restrictions reserved for Israel alone to set them apart. No, they were meant for us as well. God repeatedly called the acts listed here (vv.6-23) as, detestable or an abomination.
Our modern culture often refuses to see any aspect of sexual conduct as defiling. The only measure is immediate pleasure, not right or wrong. But sexual sin does defile us, and it does harm us. God’s laws are given for our best, not in an attempt to merely test us or boss us around. One of the reasons God brought Israel to defeat and displace the Canaanites was as a judgment against their sexual perversions. If Israel practiced the same sins to the same degree, they could also expect to be cast out of the land.
In nations that celebrate and promote similar sins today, we should expect that the judgment of God would eventually come, and "the land will vomit out its inhabitants" (v.25). God also commanded that in Israel, "Everyone one who does any of these detestable things must be cut off from their people" (v.29).
However, we are not called to be executors of God's wrath. We are followers of Christ, who was sent to save the world, not to judge it (John 3:17). And if Jesus (who is blameless in every way) was not on a mission of judgment, how can we (who still wrestle with our own sin) accuse anyone? We are to speak the truth in love when moved by His Spirit and pray for for those in need, remembering from where we were called - out of darkness and into His light.
The Truth: “For God sent not his Son into the world to condemn the world; but that the world through Him might be saved. He that believes on Him is not condemned: but he that believes not is condemned already, because he hath not believed in the name of the only begotten Son of God.” (John 3:17-18)
