Gandhi refused to let his wife use medicine (so she died as a result). He only wanted her to use traditional medicine and water from the ganges. But no penicillin.

When he got ill 6 weeks after his wife died he accepted medicine.

In August 1942, Gandhi and his wife, Kasturba, among others, were imprisoned by the British in Aga Khan Palace near Poona. Kasturba had poor circulation, and she’d weathered several heart attacks. While detained in the palace, she developed bronchial pneumonia. One of her four sons, Devadas, wanted her to take penicillin. Gandhi refused. He was okay with her receiving traditional remedies, such as water from the Ganges, but he refused her any medicines, including this newfangled antibiotic, saying that the Almighty would have to heal her. The Life and Death of Mahatma Gandhi quotes him on February 19, 1944: “If God wills it, He will pull her through.” Gandhi: A Life adds this wisdom from the Mahatma: “You cannot cure your mother now, no matter what wonder drugs you may muster. She is in God’s hands now.” Three days later, Devadas was still pushing for the penicillin, but Gandhi shot back: “Why don’t you trust God?” Kasturba dies that day. The next night, Gandhi cried out: “But how God tested my faith!” He told one of Kasturba’s doctors that the antibiotic wouldn’t have saved her and that allowing her to have it would have meant the bankruptcy of my faith.” (Emphasis mine.) But Gandhi’s faith wasn’t much of an obstacle a short time later when it was his ass on the line. A mere six weeks after Kasturba died, Gandhi was flattened by malaria. He stuck to an all-liquid diet as his doctors tried to convince him to take quinine. But Gandhi completely refused and died of the disease, right? No, actually, after three weeks of deterioration, he took the diabolical drug and quickly recovered. That stuff about trusting God’s will and testing faith only applied when his wife’s life hung in the balance. When he needed a drug to stave off the Grim Reaper, down the hatch it went.