In April 1567 the Carmelite general, Giovanni Battista Rossi (Rubeo), made a visitation, approved Teresa's work, and commanded her to establish other convents with some of the nuns from the convent of the Incarnation at Avila. He also gave her permission to establish two houses for men who wished to adopt the reform. The extension of Teresa's work began with the foundation of a convent at Medina del Campo, Aug. 15, 1567. Then followed other foundations: at Malagon in 1568; at Valladolid (Rio de Olinos) in 1568; at Toledo and at Pastrana in 1569; at Salamanca in 1570; and at Alba de Tormes in 1571. As she journeyed to Toledo in 1569 she passed through Duruelo, where John of the Cross and Anthony of Jesus had established the first convent of Discalced Brethren in November 1568, and in July 1569 she established the second monastery of Discalced Brethren in Pastrana.
These foundations were followed by an interval during which Teresa served as prioress at the Incarnation monastery in Avila, an office to which she was appointed by the apostolic visitator, Pedro Fernandez, OP. This duty she was loath to assume, and she had much opposition to face on the part of the community. However, with the help of St. John of the Cross, who served as a confessor for the nuns, she was able to bring about a great improvement in the spiritual condition of the community. On Nov. 18, 1572, while receiving Communion from the hands of John of the Cross, she received the favor of the "spiritual marriage." At the request of the Duchess of Alba she spent the first days of 1573 in Alba, and then went to Salamanca to put things in order at the foundation there. At the command of Jerome Ripalda, SJ, she started her Book of the Foundations the following August. On March 19, 1574, she established a foundation at Segovia, where the Pastrana nuns had been transferred because of conflicts with the Princess of Eboli. This marked the beginning of a second series of fonndations. The next was made at Beas de Segura in February 1575. There Teresa met Jerome Gratian, apostolic visitator of the order in Andalucia, who ordered a foundation in Seville. The bishop objected, however, and Teresa sent Ana de S. Alberto to Caravaca to make a foundation there in her name on Jan. 1, 1576, and that of the Seville convent was delayed until June 3 of the same year.
Crisis Between the Calced and Discalced. The entry of the Discalced Brethren into Andalusia was forbidden by Rossi, the general of the order, who opposed Teresa and Jerome Gratian in this matter. The general chapter at Piacenza in 1575 ordered the Discalced Brethren to withdraw from Andalusia, and Teresa herself was ordered to retire to a convent. The general put Jerome Tostado at the head of the Discalced Brethren. While the conflict raged between the Calced and Discalced Brethren, Teresa wrote the Visitation of the Discalced Nuns, a part of The Foundations, and her greatest book, The Interior Castle. The nuncio Nicholas Ormaneto, a defender of the Discalced Brethren, died June 18, 1578, and his successor, Felipe Sega, was less favorably disposed toward them. John of the Cross was imprisoned in Toledo. Against Teresa's will the Discalced Brethren held a chapter in Almodovar on Oct. 9, 1578. The nuncio annulled the chapter and by a decree put the Discalced Brethren under the authority of the Calced provincials who subjected them to some harassment. The King intervened, and four were named to advise the nuncio, among them Pedro Fernandez, OP. Angel de Salazar was made vicar-general of the Discalced Brethren while negotiations were afoot for the separation of the Discalced from the Calced Brethren and the erection of a Discalced province.
Teresa then turned to visiting her convents and resumed the founding of new ones. On Feb. 25, 1580, she gave the habit to foundresses of the convent in Villaneuva de la Jara. The brief Pia consideratione, dated June 22, 1580, ordered the erection of a distinct province for the Discalced. On March 3, 1581, the chapter of the Discalced was held in Alcala, and Jerome Gratian, who was favored by Teresa, was elected the first provincial. Teresa's last foundations were: at Palencia and Soria in 1581, at Burgos in 1582; the most difficult of all, Granada (1582), was entrusted to the Venerable Anne of Jesus.