Pennell built a small hospital at Bannu with his mother's money. In 1895 he opened a mission boarding school. Several Muslim inquirers showed an interest in baptism, but faced great opposition from relatives and other Muslims. Among his converts were Tayib Khan and Sayyid Badshah. Sayyid Badshah was shot dead soon after making his profession of faith. In 1896, Pennell was invited to visit the bandit Chakki. Pennell shared the gospel with him to such an effect that soon afterwards Chakki left his banditry; he wrote to Pennell: "I constantly meditate on your words and I have given up killing and robbery."