The Messenger of Allah salla Allahu ‘alayhi wa ‘alaa aalihi wa sallam said:

“Fasting in winter is the cold booty.” Narrated by Imam Ahmad.

They said: cold meaning easy, and because the one fasting does not feel the heat and thirst of Summer. So it is like gaining spoils of war without the heat of battle.

And it is narrated from Ibn Mas’ud may Allah be pleased with him that he said: “Most welcome is Winter!  In it the blessings descend, and the night becomes long for Qiyaam, and the day becomes short for Siyaam (fasting).”

And al-Hasan al-Basri may Allah be pleased with him said: “The best time for the Mu’min is the Winter. Its night is long so he does Qiyaam, and its day is short so he fasts it.”

And Yahya ibn Muadh may Allah be pleased with him said: “In the Winter, the night is long so do not shorten it with your sleep, and Islam is pure so do not defile it with your sins.”
And Ubayd ibn Umair, the Qadi of Mecca at the time of sayyidna Umar, may Allah be pleased with them, would say at the beginning of Winter: “O people of the Qur’an! Your nights have become longer for your reading, so read! And the day has become shorter for your fasting so fast!”

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