Confession Booth II is built in the Church for 6 Oiled Plank and 8 Bronze Detail. +7 church quality. Unlocked by Church Furniture II. Its construction site needs Building mastery 3: below that, hits do nothing.
It adds 7 to church quality. More elaborate sermons need a higher church quality. Each new best church quality counts towards the Sacred Interior inspiration. Church Furniture II also unlocks Church Shrine II.