In July 1837, Dupont, his mother, and daughter visited his maternal uncle at the castle of
Chissay-en-Touraine, where while gazing at a picture of
Teresa of Ávila, he reportedly experienced a spiritual enlightenment. Dupont joined the recently formed
Society of Saint Vincent de Paul, contributing large sums of money to it. Through his involvement with the society, he became involved in teaching night classes to tradesmen. Thereafter he remained a frequent contributor to the Little Sisters' charity for the poor and the elderly. In 1849, he helped establish nightly Eucharistic adoration in
Tours, with friends from the Society of Saint Vincent de Paul. His reputation as a Catholic activist and a helper of the poor spread within France and he was in contact with other French Catholics such as Saint
Peter Julian Eymard, who was also an active proponent of spreading devotion to the
Holy Eucharist. Dupont's charitable works and religious stance became so well known in France that he received many letters, often addressed to "The Holy Man of Tours" and the postmen knew where to deliver them. When Dupont came to Tours, the cult of
Martin of Tours had almost completely fallen into disuse. Two roads covered the location of St Martin's tomb, purposely constructed to obliterate the memory of St. Martin. Martin of Tours was, for Leo Dupont, the model of charity, and he desired to restore devotion to the Bishop of Tours, and begin the process for the eventual rebuilding of his basilica that had been destroyed by the Revolutionaries. Around 1848, following the suggestions of Mr. Dupont, the Cathedral of Tours began to restore the festivities surrounding the Feast of St. Martin on 11 November. He helped rebuild the
Basilica of Saint Martin, Tours (which traces back to 472). Dupont also promoted the use of the
Saint Benedict Medal. He was never without several on his person, which he would give to those he might meet. He purchased them by the thousands and distributed them widely. Dupont's mother lived with him most of his life in Tours and she died in 1860. ==Holy Face devotions==