'...night too shall be beautiful and blessed'

LotR as a "Fundamentally Catholic and Religious Work"    

'...night too shall be beautiful and blessed'
Fifth mansions

Growing spiritually isn't all about pain. In very general terms, you could say that John's dark nights are passages between Teresa's mansions where the soul experiences ever deeper union with God. If Frodo was apprenticed through the first three mansions before he left home, and reached the fourth mansions before he left Rivendell, throughout the Quest circumstances allowed him only dark nights.

But I believe following that, particularly during the time spent in Minas Tirith, Frodo reaches the fifth mansions and experiences spiritual joy. Teresa says that in the fifth mansions the soul reaches its spiritual betrothal with Christ. It is a foretaste of the complete union that comes in the seventh mansions, but it is temporary and not as full.

The quote that this essay's title is taken from is an example:

Now I understand why we have waited. Now not only day shall be beloved, but night too shall be beautiful and blessed and all its fear pass away!

Besides showing pure happiness, this quote also echoes John's understanding that even spiritual darkness can be blessed, which we'll see in later essays.

Tolkien has told us that Frodo didn't understand Arwen's purpose in offering him the white gem, or even the idea that he might have a need to sail West (letter #246). The kind of suffering that she speaks of is far from his mind:

But the Queen Arwen said: 'A gift I will give you... I shall not go with [Elrond] now when he departs to the Havens... But in my stead you shall go, Ring-bearer, when the time comes, and if you then desire it. If your hurts grieve you still and the memory of your burden is heavy, then you may pass into the West until all your wounds and weariness are healed...

And she took a white gem like a star that lay upon her breast hanging from a silver chain, and she set the chain about Frodo's neck. 'When the memory of the fear and the darkness troubles you, ' she said, 'this will bring you aid.'

The Lord of the Rings doesn't tell us much more about that period, perhaps because of the idea found in The Hobbit that there's not as much to say about happy times as there is about difficult times. We get a glimpse of it in “The Quest of Erebor,” which was written for the appendices of The Return of the King but omitted because of space limitations. It's a happy, peaceful time which lasts slightly longer than the trip from Rivendell to Mount Doom. Because happiness and peace don't lend themselves to exciting story-telling, and because the soul is still imperfect in the fifth mansions, on the trip back to the Shire we begin to see Frodo gradually transitioning into another difficult part of the Road.