Teresa Sanchez Cepeda Davila y Ahumada was born on March 28, 1515 at Avila, in Castile, Spain. She was the daughter of the nobles Don Alfonso Sanchez de Cepeda and Doña Beatriz.

      As a child she had a great desire to die a martyr. At the age of 18 she entered the Carmel of the Incarnation at Avila. At that time the Order followed a mitigated observance.

     Teresa suffered from illness and headaches throughout her life. After overcoming great opposition, she effected the reform of her own convent, and with the help of St. John of the Cross founded a series of houses both of Carmelite nuns and friars who were known as "Discalced" (meaning "barefooted" — they would either be barefoot or wear sandals).

      She was faithful to the Church in the spirit of the Council of Trent, contributing to the renewal of the Church. She wrote great works of ascetism and mysticism. She died during the historic night of Oct. 4-15, 1582. (Gregory XIII, in order to reform the Julian calendar, had ordered the supression of ten days of the year 1582; the day after October 4 was to be called the 15th of the same month. It was during this night of the 4th to the 15th that Teresa died.)

      St. Teresa's body is incorrupt (showing no signs of decay). Her heart is on display, and shows signs of Transverberation (piercing of the heart of which she writes about).