OK, this is the basic Creation myth for the ancient Egyptians.
At the dawn of time, Re gave birth to himself. Feeling that he was alone, Re spat, and from his spittle was born Shu, the air, and Tefnut, moisture. From the union of Shu and Tefnut came Geb, the Earth God, and nut, the sky goddess. From Re's eyes came tears, and from these came the first humans. He knitted together the mountains, he made mankind and the beasts, the heavens and earth. Each morning he rises and sails in his boat (Seket) across the sky. At night, Nut swallows him and gives birth to him once more. The serpent Apep is his foe, born from the spittle of the great mother, Neith. Re spends each night in combat with Apep, the chaos serpant.
Some believe that one day, Apep will succeed in devouring Re, and then the world will end. Others say that Re will become so old and tired that he will forget who he is. All that he has created will come to nothing. And then, perhaps, Re will give birth to himself again.