It was in school that the motorcycle-loving Naik, who had a stammer, began to be drawn towards the medical profession, says Manzoor Shaikh, a family friend who has been working with Naik's Islamic Research Foundation (IRF) for the past 21 years. He overcame the stammer while studying at St Mary's High School, Mazgaon, and he soon made Dr Christian Barnard, a South African cardiac surgeon who performed the world's first successful human-to-human heart transplant, his idol. This continued until his final year MBBS at Topiwala National Medical College and at the BYL Nair Charitable Hospital. But, all that changed one day when Naik attended a lecture by Ahmed Deedat, a South African Islamic preacher, and came away deeply impressed. "He wanted to change the world," says Shaikh.

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