Six months into medical school at the University of the Philippines, Yang Chen collapsed on his bed in tears. He hadn't cried since childhood, but tonight the frustration and isolation burst into hot, salty drops that fell to his pillow. "Why, Lord?" the student gasped. "Why did you give me such a burden for my patients and classmates when none seem interested in You? Why can't I be like other students who just go to class, come home, hit the books and then go to bed?"

The community at medical school seemed indifferent toward spiritual conversations, and those who did know Christ slighted Yang's call to a greater commitment. This was so unlike his undergrad experience, when he had grasped the Spirit-filled life, overcome shyness to obediently and joyfully share his faith, and witnessed many come to call Jesus Savior. But now, alone in his dorm room, Yang felt hopeless.

In desperation he picked up his Bible. As he read, God gently reminded him of His promises of faithfulness. "It was at that wee hour in the morning," Yang recalls, "that I came to a crisis point in my relationship with the Lord. I could finally say, 'Lord, if what You want me to do is just sow the seed of Your gospel for the next four years, then that's fine.'"

Since that lonely night in 1973, however, the seeds sown by Dr. Yang Chen have sprouted and reproduced all over the earth. "Twenty years later," says Yang, now a gastrointestinal specialist, "I'm still reaping the results of those early years of faithfulness when I hardly knew what I was doing."

But what Yang was doing was right: The spiritual principles he'd learned from Kent and Diane Hutcheson, then Campus Crusade staff members in Quezon City, he taught to others. And the others taught still others until, by the end of medical school, Yang could count 13 "generations" of disciples. This concept of winning people to Christ, building them up in their faith, and sending them to win and build others is called spiritual multiplication. And Yang majors in it.

Building on these vintage Campus Crusade principles, Yang went on to found the Medical Strategic Network, which trains doctors, nurses and dentists (and their spouses) to use their medical platform to reach the world for Christ, one life at a time. The Network began first in the Philippines, then grew to the United States and then on to continents far and wide.

Not everyone understands the strategy, however. "Because working with only a few people doesn't seem impressive," says Yang, "people cannot always see the importance of spiritual multiplication. It's much easier to go from program to program."

The payoff comes as disciples begin to "reproduce" themselves in the lives of others and people sprout up, until a vast network exists. "Then you turn them loose," says Yang, "and God uses them wherever He wants to position them."

Occasionally Yang hears from different people in the generational links now positioned around the world. Dr. Ding Miguel, for instance, who worked alongside Yang in the '70s, runs government and private programs to help Filipino villagers. Another couple serves as medical missionaries in Vietnam. Yet a third in Africa.

Somewhere in the lineage, a dental student in the Philippines shared the truth of Jesus Christ with Josephine Wong, now a neurologist in Taiwan. On page 16 you can read how the gospel flowered in her life and urged her into ministry. Dr. Chen himself lives in Loma Linda, Calif., where he oversees the Medical Strategic Network.

When Yang graduated from medical school, four years after that lonely night of resolution in 1973, he had shared Christ's message of hope with virtually all of his 120 classmates, one by one by one. "I never would have envisioned these effects," says Yang today, "even if I had tried to dream of it."

In God's economy, spiritual multiplication adds up.