Two of the best sermons I ever heard were not preached inside the walls of a church, during a revival or at an evangelism conference. The sermons weren’t on a podcast or live-streamed over the Web. There was no pulpit, no love offering, no quiet mood music during the invitation.

These two sermons were living and active and had names: Jeff and Dow. They were preached on a daily basis through the lives of two men in my dorm at Clemson University.

I remember my first night at college. I had just met my new roommate from Jacksonville, Fla. We got to know one another, and then he did something very strange. He climbed up into his top bunk and started reading his Bible. I thought to myself, “Does he know it’s not Sunday?” I began to listen as the sermon developed over the coming weeks. There was something different about this guy, and I wanted to know what it was. He actually lived out the sermons that I remembered being preached at my church while growing up. He made decisions based on Scripture and actually enjoyed life, too. Why did he live this way?

Dow was two years older than me and lived on my hall. I listened to the introduction of his sermon the first week I was at school. You would have thought it was just a conversation among guys, but I noticed something very different. What I witnessed was a guy who was fun to be around, loved Jesus and was open about what he believed. His roommate, Lopez, was just like him. I thought to myself, “What’s up with these guys?” The sermon continued over the next few months as I watched Dow interact with others. His magnetic personality attracted believers and nonbelievers alike. It was not uncommon to see those far from God engaged in laughter and conversation with him. He treated them with grace and pointed them to Jesus. Why was he so different?

Dow and Jeff lived questionable lives. Missiologist Michael Frost describes a questionable life as one that arouses curiosity among unbelievers, which leads to questions and faith-sharing. Their lives were sold out for Jesus, countercultural and full of joy. Their lives provoked me to ask questions, and their answer was simple: They loved Jesus and had surrendered their life to Him. I wanted that same joy.

I surrendered to Jesus at the campus ministry I attended at their invitation. The sermon that night was pretty compelling, but not as powerful as the sermon I had been listening to for the past three months.

Paul charged Timothy to preach the Word in season and out. The most compelling sermon you will ever preach is a life lived out in total surrender to Jesus. When others ask why, be ready to answer. Be the sermon that changes someone’s life. Live a questionable life.