Abu Sa`id Al-Khudri (May Allah be pleased with him) reported: The Messenger of Allah (sallallaahu ’alayhi wa sallam) said, "Every slave of Allah who observes Saum (fasting) for one day for the sake of Allah, Allah will draw his face farther from Hell-fire to the extent of a distance to be covered in seventy years.'' [Al-Bukhari and Muslim].
Commentary:
"Every slave of Allah'' includes men, women, the free and the unfree, because they are slaves of Allah. The Hadith highlights the excellence of fasting for the sake of Allah which will serve, on the Day of Resurrection, as shield against Hell-fire.
Abu Hurairah (May Allah be pleased with him) reported: The Prophet (sallallaahu ’alayhi wa sallam) said, "He
who observes fasting during the month of Ramadan with Faith while
seeking its reward from Allah, will have his past sins forgiven.''
[Al-Bukhari and Muslim].
Commentary:
"Sins'' here means minor sins which relate to the Rights of Allah.