[m.]; the Fourth “Day of Creation,” described in Bereshit 1:14-19
And G-d said, “Let there be light-producing heavenly bodies, to divide between the Day and the Night, and to be markers for special times, and for days and for nights. And they should also come to be illuminating bodies in space, to provide light for the Earth. And it was so.
And G-d created the two Great Lights, the Great Light to rule during the Day, and the Smaller Light to rule during the Night, and the Stars.
RASHI cites a Midrash on the above verse, which contains an apparent contradiction. First the verse speaks of two Great Lights. Then it speaks of the Sun as the Great Light and the Moon as the Smaller Light!? Were they equal or unequal? The Midrash comes to teach a moral lesson, that originally the Sun and the Moon were of equal size, but the Moon complained, “Two Kings cannot wear one crown! Both the Sun and I cannot both be Kings!” G-d said, “You’re right; go reduce yourself to be the smaller light.”
Another resolution of the apparent contradiction, with a scientific bent, obtained from “In the Beginning,” by Professor Aviezer, is that the Moon was always much smaller, but it was created by G-d in just the right way that it had the same “apparent size” as the sun. Such that in a solar eclipse, the moon was just the right size and just the right distance away from the Earth to completely block the rays of the sun.
An Evening and a Morning passed, completing the Fourth Day.