Teresa of Avila, a renowned sixteenth–century Spanish mystic, received the vision for The Interior Castle one Sunday in 1577. In this signature work, Teresa uses the castle as a symbol for the interior life to describe her mystical experience of the presence of God. Her humble and straightforward treatise invites readers on a spiritual journey to enter into the deep places in their soul where they will find God.

"The soul of the just person is nothing else but a paradise where the Lord says he finds his delight. So then, what do you think that abode will be like where a King so powerful, so wise, so pure, so full of all good things takes his delight? I don't find anything comparable to the magnificent beauty of a soul and its marvelous capacity." –– Teresa of Avila