Teresa of Ávila wrote the Interior Castle in 1577, at the age of sixty-two, under obedience to her confessor. She completed it in five hours of inspired writing — a fact she noted herself with some bewilderment. She was not a professional theologian. She was a Carmelite nun who had spent decades in prayer, and who had been asked, not for the first time, to write down what she had found.

The image she begins with is one of the most arresting in the whole of Christian mystical literature. Imagine the soul, she says, as a castle made entirely of diamond or very clear crystal, in which there are many rooms, just as in heaven there are many dwelling places. At the centre of those rooms is the innermost chamber, where the most secret things pass between God and the soul. The soul does not have to travel to find God. God is already at the centre. The question is only how far in you are willing to go.

This image does several things at once. It affirms the dignity of the soul — not as an earned achievement but as a given. The castle is made of crystal: it is already beautiful, already ordered, already luminous. Sin does not destroy the castle. Teresa is clear about this. What sin does is darken the crystal, cloud the rooms, make the soul unable to see its own beauty or the light that shines at its centre. The work of the spiritual life is not construction. It is clearing.

The first mansions — the outer rooms of the castle — are where most people live most of the time. They are inside the castle, which is already a great thing. They have faith, they practise some form of religion, they are not entirely indifferent to God. But they are so preoccupied with the activity of the outer courts — with the noise of the world, with their own concerns, with a thousand small attachments — that they rarely pause to go further in.

Teresa does not condemn this. She understands it. She spent the first twenty years of her own religious life in roughly this state — technically faithful, periodically fervent, but fundamentally distracted. What changed her was not a single dramatic conversion but the slow accumulation of honest prayer: the willingness to sit with God in silence even when nothing was happening, even when she felt nothing, even when the silence felt like absence rather than presence.

This week your only task is to enter the castle. To sit down in the interior. To be still. Teresa does not ask you to feel anything, achieve anything, or produce any particular spiritual experience. She asks you to show up — to the reality that God is at the centre of who you are, and that the way toward that centre is through silence and attention.