There are good ways, tacky ways, and flat-out wrong ways to use pop culture for Gospel presentation. Evangelism doesn't validate everything and anything.
A few years ago, we attended a Christmas play at a local church. They were putting on a re-enacted Mayberry script, in which Andy presents the Gospel to cranky old Mr. Weaver. Maybe you remember the episode.
The church that night was packed. It was a pleasant evening. I can't say that sort of presentation is my cup of tea, but the Gospel was presented accurately. So, if someone came to Christ because of it, then I thank the Lord for that. After all, I was first meaningfully exposed to Christianity through Peanuts (I'm sorry, Willow Grove Presbyterian Church, but I don't remember a single thing from Sunday school, other than the thick white paste we used to glue down the cut-out apostles).
The Mayberry play was a tad corny, but it wasn't a defilement of the Gospel. There's no built-in anti-Christian quality built into The Andy Griffith Show.
Well, what about Santa?
I've seen kneeling Santa figurines in creches next to the shepherds and wise men, adoring the Christ-child figurine. That's just weird, because it erases a line between Biblical, historical reality (Jesus Christ and the holy night of his birth) and a mythological fantasy (Santa). How would we feel about a painter putting the Easter Bunny hopping amidst the dead of Gettysburg? See what I mean? The very idea is terribly tacky at best, and blasphemous at worst.
However, I've seen Santa used in art pieces. Not plunked down in a creche, but just the Santa picture making some sort of pro-Bible, "Christmas is not about Santa" statement. If Santa is handled in an art piece symbolically, not inserted absurdly into a real event (the nativity), I can see that as worthwhile use.
You know, I can even imagine writing a play in which Jean-Luc Picard, the atheist captain of the USS Enterprise, realizes through the influence of the Bible, the error of atheism. Paramount studios would never let you stage it, but I can imagine a story like that. But, if you did write such a story, you should know that you were spitting on everything Gene Roddenberry believed in. Roddenberry was a fervent, fanatical atheist. There is a humanist message embedded in the DNA of Star Trek, and Christianity clashes directly with it.
imagine a TV program in which various "gods" (Zeus, Baal, Athena, whoever you can think of) talk about, and actually interact with, Jesus. Maybe, at the end, you have them all bow down to Him. Would that be excellent example of "contextualized" evangelism? Or would be it a crossing of truth-lines that should never be crossed? I say it's the second.
The inherently evil nature of idolatry, combined with attributing reality to any "gods" at all (when Paul in 1st Corinthians say the gods do not exist), are crucial issues. It would be worse than depicting, say, Mickey Mouse talking to Jesus, (even though I believe doing that would be ridiculous), because Mickey Mouse in his basic nature doesn't carry an anti-Christian meaning. He's just a plucky comical mouse who has comical adventures.
*This is why the VBS puppet plays I used to write for Mountainside Chapel never had Jesus in them. The little characters talked about Jesus, but Jesus himself was not a character in any of the plays I wrote).
The potential for creating confusion is huge, especially in children, regardless of whether it's done in the name of reaching people for Christ.
One must be very, very discerning about using pop-entertainment culture in the work of evangelism, especially if the pop culture thing you want to use already has a distinct philosophical or religious "gospel" of its own. "The Force", for example, is not a neutral thing. The Force is pantheism, and it is foundational to occult/wiccan thinking.
But doesn't the Bible show the Bible writers using pop-cultural ideas and words to present the gospel? Consider how the Apostle John used the Greek word logos in John chapter 1. To the Romans and Greeks, the word logos referred to a universal, impersonal force of rationality, like a force of math, that ran throughout the universe and held everything together.
So in John 1, John took that distinctly pagan, philosophical, pop word, and he used it. Doesn't that justify using all pop-culture for evangelism? But John did not say, "Look, Romans, the logos that you believe in really points you to Jesus Christ...". No, John rejected the Greco-Roman meaning of the word.
John instead said that the logos was a person (not a force), a member of the Godhead (not part of nature), and that He became a human being! By the time John was done with the word logos, he had completely re-defined it. I bet the Romans were irritated by John's total re-definition of "their" word, in a "who do these Christians think they are" kind of way. John in effect was demanding that the Romans abandon their false god, the logos.
In the same sense, Christianity requires us to abandon the idea of The Force. The Force cannot lead us to Jesus Christ. The Force isn't a good idea being misused, which is sometimes the case. No, the Force is a bad idea, bad from top to bottom. The Christian stance toward the Force should be to expose and refute it, not try to "redeem" it. You wouldn't enlist Zeus on behalf of Christianity, and you cannot enlist the Force for the same reasons.