Following my last theory (Blog below), that of the Prometheus movie and its relation with greek mythology, now I have the theory for the upcoming Alien: Covenant film.
Prometheus was about the origin of mankind, created by the titan Prometheus (Good engineers) who give the gift of Fire, Technology and Science. but also the titular ship. Now, Ridley Scott say Alien: Covenant is about the origin of the Xenomorph, and following the relationship with the myth and Hesiod account of the story...
Covenant is again the name of the ship, named this way because is the first ship produced by the merged Weyland and Yutani companies, a pact or Covenant. But in a double meaning, may also refers to the first part of the Prometheus' story...
The gods and mortals have arranged a meeting where the matter of the division of sacrifice to the gods have to be settled. Stablishing precedent for a pact or COVENANT between gods and humans. But Prometheus tricked the gods into take the worst part of the sacrifice, and that enraged Zeus. Anyway, this event gave Zeus an excuse to ven his anger on mortals.
Whatever the terms of the pact between Engineers and ancient Humans was, the trick was the reason for which the Engineers want to destroy humanity, first by keeping Fire (knowledge, science and technology) from being used by humans, and after Prometheus stoled and returned it to man, by sending a Pandora "All gifts" (or Anesidora "She who bring all gifts") disease, despair, war and death to them inside a jar (Black goo in steatite vases).
The murals in the temple shows a lifecyle, starting with facehuggers creatures impregnating a humanoid. maybe the pact at Mecone was that one or some representatives of the species are meant to be sacrificed in order to create life (Chestbursting ), but Prometheus (good engineers) tricked Zeus (bad engineers) into get facehugged, and that's what the mural represent: A reminder of the trick and the reason to them for hate us. Then the gods took the original organism and weaponized it.
Works and days, the poem writen by Hesiod which contains the story of Prometheus and Pandora, is seen as a work about the agrarian crisis in mainland Greece, which inspired a wave of Colonial expeditions. Is similar to the space colonization seen in the Alien and Prometheus timeline at the dawn of the 22st century. Further more, Works and Days is a farmer's almanac, which is a publication about moon and planet cycles, sustainability, farming and animal keeping, similar to the steps to terraform a planet (exoplanetology, atmosphere processing, food production and cattle).