How does Gandhi display his beliefs in his personal life and political works?

Gandhi lived his beliefs. As a Hindu strongly influenced by monastic traditions, as well as Christianity and Jainism, Gandhi believed in the spiritual importance of living as simply as possible. Over time, he gradually stripped away more and more material goods. As a successful lawyer with a house in South Africa, he ended up sending all his money to his brother. By the time of his death, he literally owned only ten items, including his sandals, walking stick, reading glasses, bowl, and spoon. This simplicity, while being rooted in his spirituality, also sent a strong political message to the British that he was not like them and did not admire their ways.
Gandhi also believed very strongly in the spiritual purification of the right diet and lived on a meagre vegetarian diet of rice and beans, which he called "pulses" in his autobiography. When he had asked for extra salt for his food while in prison and was denied, he found this was a form of spiritual teaching, showing him he did not need his food seasoned with salt.
All of this, he believed, cleared his mind and body for the spiritual and political task of liberating India from British rule by using non-violent political action. He called this practice of spiritual non-violence "satyagraha." He trained his disciples in it and wouldn't allow them to engage in political protest until he felt sure they truly had abandoned a desire for violence.