It is narrated from Hazrat Anas (may Allah be pleased with him) that when the Prophet (peace and blessings be upon him) arrived in Madinah Munawwarah, the climate there was hot, due to which people were afflicted with fever. One day, the Prophet (peace and blessings be upon him) entered the mosque and saw that people were performing prayer while sitting. The Prophet (peace and blessings be upon him) said, "The reward for performing prayer while sitting is half of that for performing it while standing." Upon this, people hurried to stand up and perform the prayer.