Light and Darkness
Some myths appear in many forms, associated with rising and setting. The Greek rendering is that Kronos (Time) married Rhea and devoured all his children at birth except Zeus (Air), Poseidon (Water), and Hades (the Grave), which three Time cannot consume.
An earlier tradition is that Kronos devoured all his progeny except Zeus, for whom a stone wrapped in swaddling clothes was substituted and promptly swallowed, the child Zeus being secreted.
On arriving at adult age, Zeus compelled Kronos to disgorge, first the stone, then the other children in succession. The literal meaning being that of night covering up or swallowing the world, the disgorging being the sunrise.