My sister’s family gave me a gift this year while we were on furlough in the States—a message t-shirt. I have never been one to wear slogans. In fact, I can think of only one other message shirt I have ever worn. A friend gave me a shirt that said, “I Believe in the Big Bang. God said it, and BANG it happened.” Other than that one, I haven’t worn sports team names or other advertising. I frankly don’t like the idea of being stereotyped around a single theme. (Though I really liked a shirt I saw this summer that said, “Clones are people two.”)

The shirt my sister gave me reads: “I love haystacks.” It certainly was an unusual stereotype to wear around my neck! Okay, I thought, I’ll try this out. First it was at a gathering at my parents’ house. About 35 people were present. My mom was serving haystacks, so this was going to be a big winner. Sure enough, every person in the house made a comment. So the next day I thought, I’ll wear this to the zoo and harvest the reaction of the general public. It was an experiment day after living my whole life as part of the non-t-shirt-wearing control group.

Having a message visible to the world was a new experience. It was as if I was one of the zoo exhibits! I had no idea t-shirts received so much eye time! They are like candy for the curious human mind. It seemed like every person we passed stared at it and tried to crack the mysterious riddle: “I love haystacks.” I could see the looks on their faces as they asked themselves, What does this mean? Why is this moderately sane-looking middle-aged man wearing this strange message? Who could possibly guess there were a thousand happy Adventist occasions involving pinto beans hidden in that code on my chest?

We were standing near the gorilla exhibit when it finally happened. One of a group of ice-cream-cone-licking teenage girls called out, “Pardon me sir, what does your shirt mean?” It was then I had my epiphany. Riddle evangelism! Yes, it could work!

Later that day, I was exiting the aquarium when I saw a girl looking at my shirt and mouthing the words over and over. Then she said out loud to her friends, “I love haystacks.”

“What?” one of them said.

“Oh, I was just thinking out loud,” the girl replied. “That guy had it on his shirt.”

I started thinking about how I could use riddle evangelism in Turkey. Maybe I could wear a t-shirt with something mind-bending for Muslims like, “I love the Judgment.”

As I thought about what riddle might have shock value in Turkey, I remembered an incident a few years ago when I told an older Turkish gentleman, “I know I will be in heaven with God. He has given me a green light and has told me I am in. I am family.” The man was amazed and repeated it over and over. Several months later, he and I were walking through town together. We met an elderly woman he knew. He stopped and repeated my words verbatim to her. So I guess assurance has shock value. How could I use it for riddle evangelism?

On my way home from furlough, I stopped in Germany to preach half a dozen sermons for a youth street-evangelism event. I was surprised and delighted to learn these Germans were already far advanced in the art of riddle evangelism and were practicing it successfully. I could learn from them. Every day, they would go out into the streets and create public curiosity. For example, they made a statue like the one in Nebuchadnezzar’s dream and stood it in the street. As people walked past, the youth asked them, “Do you know what this means?” It created quite a bit of interest and excellent opportunities to tell people the whole prophecy of Daniel 2.

Another outreach was a series of mysterious symbols on a set of eight white boards. Different from the bridge-and-cross napkin-type drawings people often use to share the gospel, these symbols were not clearly discernable as Christian. The panels were entirely inductive. The youth simply stopped people in front of the panels and asked, “What do you see here?” Then, through other lead questions, the passersby would start to deduce meaning from the collection of seemingly random symbols. Through the help of the picture panels, they confessed there were questions in life only a higher power could answer, the God who created us. Another series of eight panels helped people recognize sin and its single solution.

Since I didn’t know German, they decided to put me in a giant cylinder, like a toilet-paper tube, so I could walk around as a mobile advertisement for the evening meetings. I enjoyed this immensely. All the people in the street were most entertained by this wandering tube with feet.

After exiting the tube, I noticed a young man wearing a black t-shirt advertising the rock group Metallica and their album, Master of Puppets. I thought, Hey, this guy is wearing a riddle and likely doesn’t even know it. As I walked up to the guy, I saw he was wearing an upside-down pentagram around his neck. “Hi,” I said, “I was wondering if you can tell me who are the puppets your shirt is talking about?”

“People,” he said. (It was kind of obvious since there were gravestones all over his shirt.)

“I see each of those graves has a string attached that goes up to some hands. Who do you think Metallica means by those hands? Is that the ‘Master?’” The guy looked at me like I was crazy for asking. He avoided saying Satan, but then, after a few more questions, he acknowledged it was probably the intent of the rock group. Now I got him thinking about the riddle: “Why would Satan want puppets?” We talked for another five minutes.

It seems to me that Christ was using riddle evangelism when He quipped, “It’s easier for a camel to go through the eye of a needle than for a rich man to enter heaven.” And also when He said, “Tear this temple down, and I will build it again in three days.” It was a shocking puzzle that left His listeners without a clear instant answer, but much to think about. It was the same thing God did in Babylon when he wrote a jumbo t-shirt message: “Mene Mene Tekel Upharsin.” I think it is the curiosity-inspiring effect Ellen White hoped the name Seventh-day Adventist would have for every Christian who encountered it—a riddle compelling enough to beg for someone to crack it.

Now I must find that troubling riddle for Turkey. Frankly, it is a bit like looking for a needle in a haystack. Good thing I love haystacks!

• Twitter