I coach an accountant tentmaker who is determined to love despite the odds. His wife is unfaithful. He tells me, “I will be faithful.” She abuses him verbally and physically. He tells me, “I forgive her. She just hasn’t gotten the gospel yet.” She threatens him. He says to me, “I am hurting, but I won’t give up. I will love her as Jesus loves me.”

Romans 12:9 says, “Love must be sincere.” How can we get that kind of sincere love?

Our English word sincere comes from the Latin sincerus, which means “without wax.” Odd indeed! What’s the connection? It stems from a practice of early Roman merchants who set their clay jars out for sale. If a crack appeared in one, they would fill it with wax the same color as the clay so a buyer would not be aware that it was cracked. A shrewd wholesale buyer would put the jars out in the sun so that any wax on them would melt, revealing the cover-up. So the honest merchants would test their wares this way and mark them sincerus—without wax. That’s why some Bibles translate it, “Let love be genuine.” J. B. Philips writes, “Let us have no imitation Christian love.”

The sincerus principle is why tentmaking—witness in the context of daily work—was so effective for Paul and is still the cornerstone of church growth today. There is nothing phony about a tentmaker! There is no cover-up or identity fraud. For the tentmaker Christian, witness isn’t bought, contrived or glued onto a life. Tentmakers are exactly what they appear to be—skilled workers who have hope through Jesus. The people they befriend are attracted to that authenticity.

I teach GoTential tentmakers that all witness begins with love. But sincere love doesn’t come naturally; it is a gift of looking at people through the eyes of Christ.

Earnesto, an Adventist tentmaker engineer working in Oman, told me of his slow and steady love for a coworker. He didn’t love his Muslim colleague, but he knew Jesus did. So every few days he told the man, “I have a rich Friend who really loves you.” This went on for over a year as he repeated this mysterious statement again and again. It was a very strange thing to tell someone, and the man grew extremely curious, as you might imagine. “My Friend admires you and talks to me about you all the time,” Earnesto told him. When the man got into a financial pinch and needed about $1,000 dollars, Earnesto said, “I will talk to my Friend who loves you. Maybe He can help.” That day, Earnesto was surprised when someone who owed him about a thousand dollars repaid the long-forgotten debt. Earnesto immediately went to his Muslim colleague and said, “The Friend who loves you gave this to me to give to you.” The Muslim man began to cry and said, “Who is your friend? Is it Jesus?” Earnesto said this was one of the greatest days of his life, because the man had discovered Jesus through simple love.

We can try to love people with all of our heart. The problem is that our hearts aren’t pure enough. Sincere love begins when we love people with all of Jesus’ heart. First Corinthians 13 reminds us that love is patient and kind. Those traits aren’t natural; they are supernatural. They begin at the cross of Christ, the only place on earth where the selfless life can sprout.

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