The polished mirror

The heart is a mirror. It does not need to acquire anything; it needs the rust taken off. Polish it — by remembrance, by scrupulousness, by not lying to yourself — and it reflects what was always in front of it. The metaphor runs from the earliest masters through Ghazālī and Rūmī.

The door's namesake, and a whole doctrine of the person. Compare the Kabbalistic aspaklaria, the speculum through which the prophets saw — Moses through a clear glass and everyone else through a dim one — and both traditions turn out to think the instrument is a surface, and the work is on the surface.