Ibn Mas'ud related that Allah's messenger slept on a reed mat and got up with the marks of it on his body, so Ibn Mas'ud said, "Messenger of Allah, I wish you would order us to spread something out for you and make something." He replied, "What have I to do with the world? In relation to the world I am just like a rider who shades himself under a tree, then goes off it and leaves it." (Ahmad, Tirmidhi and Ibn Majah transmitted it.