It seems as if we're making a real art of substitution in America these days. High on the list of the dieter's list, for instance, is the "sugar substitute". We don't want to give up sweet, so we'll find something that will substitute for sugar. Oh, it's not easy. That one has been shown to cause cancer and this one has been shown to cause memory loss. I suppose if you used them both you would get cancer, but it wouldn't matter since you couldn't remember.
We're all aware of the "surrogate mother" concept. In this approach to producing children parents will find a substitute sperm, substitute egg, or maybe just a substitute womb.
Philosophically, modernism was once king. Modernism believed that careful, rational thought could provide the answers to all of life's questions. We now have a substitute: post-modernism. Replacing modernism is the complete rejection of rationalism. We've substituted "I think" with "I feel and, therefore, it's right."
For the first 200-or-so years of our national history, the Judeo-Christian ethic has been our moral guide for the most part. Well, not any longer. We've found a substitute. In sexual matters, instead of a sexual morality that called for marriage before sex we've substituted "adult" and "consent" as the only requirements. Anything else is fine. And they're working on removing the "adult" part. Some don't want to limit it to "human". Of course, it has been a long time since we substituted the primary purpose of sex from procreation to recreation.
Our country was founded on a Bill of Rights that outlined necessary protections of basic rights against government encroachment. We've started substituting new rights for these old ones. Last year the courts substituted gay mirage for the longstanding, historical, traditional definition of marriage ... in the name of "equal rights". States have moved to put protections in place for religious rights promised by the First Amendment, but "gay rights" preclude those. When a clerk in Kentucky refused to issue marriage licenses to same-sex couples, there was an outcry. When a gay judge in Texas refused to perform heterosexual marriages, there wasn't a peep. The florist who suggested that her gay friends use a different florist for their marriage ceremony found that exercising her First Amendment rights to the free exercise of religion cost her her business. As have others. The Bill of Rights was a nice idea, but today we're making some substitutions.
It certainly isn't new, but most don't really notice the substitution of "love your neighbor as yourself" (which even unbelievers applaud) with "love yourself before your neighbor". I suppose that's why we're doing this substitution with a vengeance.
Then there's the gospel. Most Americans in the mid-20th century had heard it. Today, it's a mangled mess. "Hell" has become "unpleasant circumstances" and even "a better place to be" ("I wouldn't want to be in heaven if my friends, family, or dog wasn't there."). "Heaven" has become little better than the Islamic "72 virgins" where all my personal preferences are catered to. The road to avoiding one and achieving the other is basically "Be all you can be." We've selected a substitute gospel with a substitute Christ to avoid a substitute Hell and achieve a substitute Heaven.
Sugar substitutes can harm your body. This final substitute will destroy your soul. Substitutions are not always a good idea.