Clare was born about the year 1268, a decade after the Great Union that gave rise to the modern Augustinian Order. When still but a child, only about six years old, she went to live with her sister Joan who was the leading member of an enclosed community of dedicated women in the area. In 1290, under the guidance of the local bishop, they established a new convent of regular observance, to be known as Holy Cross Abbey, under the Rule of St. Augustine. Here Clare made her profession of vows. A year later Joan died and, no doubt because of the reputation she had already established among the Sisters and despite her youth, Clare was chosen abbess. She was to govern the convent until her death in 1308.
Clare led her community by both word and example. According to her biographer she «became a mirror and a norm of holiness». She stressed humility and simplicity of life, poverty, austerity and manual work. Though lacking in formal education, Clare had a deep understanding of the spiritual life and the ability to communicate this to others. She was noted for «the spirit of prophecy by which she read the secrets of the heart». Her biographer continues: «She knew the past, discerned present realities and foretold the future; she understood everything clearly in contemplation of him who is the splendour and the reflection of the Father’s bright glory».
We are told that she was blessed with infused knowledge and that she powerfully defended the truths of the Faith. Learned theologians and Church leaders of the time were known to consult her on occasions. Clare was particularly devoted to the Passion of Christ and she is sometimes known as St. Clare of the Cross of Montefalco. She would say to her Sisters, «I do not need to wear a cross outwardly, for I bear the Cross of my crucified Lord Jesus Christ in my heart». After her death the Sisters were curious about her assertions and «when her heart was examined they found depicted there symbols of the Passion of Christ».
Shortly before her death Clare called all her Sisters together and gave them her last instructions. Her biographer quotes words that reflect the Rule of St. Augustine: «My dearest daughters and sisters, in union with the death of Christ our crucified Lord I commend all of you and my own soul to God. I give back to the Lord you and the burden I have borne among you. Be humble, obedient and patient, and he united in love. Live so that God may be praised in you and so that the work the Lord God has accomplished in you may not perish».
Clare died on 17th August, 1308. Her incorrupt remains are venerated in the Augustinian convent chapel in Montefalco. Venerated as a saint from her death, and indeed during her lifetime, Clare was officially canonised by Pope Leo XIII in 1881.