Right-clicking on the lectern while holding a book will place it on the stand. Right-click on a book on the stand to access the Book's Linking panel to another Age.
While a book is on the lectern, it's immune to any damage it would be receiving if it were simply placed on the ground. However, rain will still damage the book. This will help reduce the chance of accidentally destroying the book and losing an age.
The Lectern is an alternative to Bookstands, and looks best when placed at eye height on top of another block.