Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: Sayyiduna Umar bin Khattab (may Allah be pleased with him) came to the service of the Prophet (peace and blessings be upon him). At that time, you were lying on a mat, the marks of which had appeared on your side. Sayyiduna Umar (may Allah be pleased with him) said: O Messenger of Allah (peace and blessings be upon him)! If you used bedding softer than this (it would be appropriate). The Prophet (peace and blessings be upon him) said: What connection do I have with the world, and what connection does the world have with me? By Him in Whose hand is my soul! My example and the example of the world is like that of a rider who, while traveling on a hot day, stops for a short while under the shade of a tree, and then leaves it and moves on.