Fasting produces spiritual peace and exhilaration. During the month of Ramadhan an additional ibaadat, viz., Taraaweeh Salaat, has also been decreed. The performance of Taraweeh is Sunnatul Muakkadah which is an act, the performance of which is obligatory although it may be omitted for a valid Shar'i reason. One who is neglectful of Sunnatui Muakkadah is guilty of sin and is termed in the Shariah a 'faasiq'. Taraweeh reduces sleep to some extent.
Sleep is an act highly pleasing and loved by the nafs.
Hence, by means of Taraaweeh Salaat one strives against the nafs and in so doing the nafs is disciplined. This ibaadat of Taraweeh is an act which is greatly efficient in the spiritual training of the nafs. During the month of Ramadhan, Allah Ta'ala has united two great and highly efficacious spiritual exercises in the form of fasting and Taraaweeh Salaat. I prevented him from eating and carnal desire. Therefore, accept my intercession on his behalf.