Ja'far ibn Muhammad reported that his father said

"'A'isha was asked: 'How was the mattress of Allah’s Messenger (Allah bless him and give him peace) in your home?' She said: 'It consisted of tanned hides stuffed with fibers.' Hafsa was also asked: 'What was the mattress of Allah’s Messenger (Allah bless him and give him peace) in your home?' She said: 'Coarse woolen fabric that we folded in two for to sleep. Then one night I said: ‘If its two folds were four, it would be softer for him,’ so we folded it for him in four folds. Then, when he woke up in the morning, he said: ‘What did you spread out for me tonight?’ She said: 'We said: ‘It is your mattress, except that we folded it four times. We said it would be softer for you.’ He said: 'Restore it to its original condition, for its softness prevented me from performing my ritual prayer tonight!'"