It is narrated from Sayyiduna Ka'b bin Malik (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: The example of a believer is like that of the grains of a crop which the wind blows; sometimes it makes them level and sometimes it throws them to another place, until their appointed time comes. And the example of a disbeliever is like that of rice which stands firm on its root; nothing can shake it until it is taken down all at once.