Sick with Desire

From the final chapter of Bunyan's remarkable book:

Now as they walked in this land, they rejoiced more than they had in any other part of the journey.

And as they came near the Celestial City, they could see that it was built of pearls and precious stones and that the streets were paved with gold. The natural glory of the City and the sunbeams' reflection on it made Christian feel sick with desire. Hopeful also had a few bouts of the same sickness. The sickness was so great that they had to rest from their journey while crying out because of the deep pangs of desire.

Finally they got some of their strength back and were able to bear their sickness.

--The Pilgrim's Progress (ed. C. J. Lovik; Crossway 2009), 212