מדרשים על אדם הראשון וקלנדס על תקופת החורף | Midrashim on the Origin of the Festival of Kalends on the Winter Solstice by the Primordial Adam

Our Rabbis taught: When Adam HaRishon (primitive Adam) saw the day getting gradually shorter, he said, ‘Woe is me, perhaps because I have sinned, the world around me is being darkened and returning to its state of chaos and confusion; this then is the kind of death to which I have been sentenced from Heaven!’ So he began keeping an eight days’ fast. But as he observed the winter solstice and noted the day getting increasingly longer, he said, ‘This is the world’s course’, and he set forth to keep an eight days’ festivity. In the following year he appointed both as festivals. Now, he fixed them for the sake of Heaven, but the [unenlightened] appointed them for the sake of star worship. . . .


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