Do good deeds for God's sake; Fast on days prescribed by Him; Show gratitude towards His blessings; Be faithful to Him always.

This hadith speaks about the reward that comes from fasting one day in the cause of Allah. It was narrated by Abu Saeed Al-Khudri that Prophet Muhammad said that whoever fasts one day in the cause of Allah will be rewarded with a great distance between them and Hellfire. This means that if someone fasts for a good reason such as to please God or to help others, then they will be greatly rewarded by God. The reward is so great that it is like having seventy autumns between you and Hellfire! This shows how much God values those who do good deeds for His sake and how He rewards them generously.