St Thérèse's "genius consists in leading us to what is central, essential and indispensable," the pope wrote in an apostolic letter published Oct 15.

The young saint, whose life and writings focused on love and following a "little way" of holiness, "shows that, while it is true that all the Church's teachings and rules have their importance, their value, their clarity, some are more urgent and more foundational for the Christian life," he said.

"From heaven to earth, the timely witness of Saint Therese of the Child Jesus and the Holy Face endures in all the grandeur of her little way," Francis wrote.

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