Here’s my take on the Ziz (or Ziz Shaddai, or Bar Juchne, or Bar-Yuchnei), which is the largest aerial creature ever created by God in Jewish mythology ! Considered the protector of all avian creatures, it is sometimes represented as a giant griffin, sometimes as an enormous bird, often alongside his "cousins" the Behemoth and the Leviathan, respectively associated to earth and waters. But unlike the latters, Ziz doesn’t have any physical description in the Hebrew Bible.
Indeed, as far as the Old Testament is concerned, Ziz is only mentioned twice, first in Psalm 50:11: “I know all the birds of the mountains and Zīz śāday is mine.”, then in Psalm 80:13-14: “The wild boar of the forest ravages, and Zīz śāday feeds.” Moreover, many translations of the Scriptures result in the name "Ziz" being completely removed from the above-mentioned excerpts, for example: "I know all the birds of the mountains, And everything that moves in the fields belongs to me ”, and again: “The wild boars of the forest have destroyed it, and all kinds of wild beasts have grazed it.” It is therefore not surprising that the Ziz is so little known, compared to the Behemoth and Leviathan, which are described in the Book of Job.
It is ultimately in books other than the Bible that we can learn more about this creature, in particular in the Talmud, a fundamental text of rabbinic Judaism compiling discussions on a wide range of subjects, notably on Jewish myths. One of the texts constituting this corpus, the Aggadah, sheds light on the etymology of the creature's name, the latter coming from the great variety of tastes of its flesh : it tastes like this ("zeh") , and it tastes like that (“zeh”). This same text transcribes a legend in which two sailors once saw the Ziz, whose head reached the sky, and whose feet were submerged in the surrounding waters. The travelers therefore thought that the water was shallow there, and thought of bathing there. But a celestial voice then warned them that the depth of the place was such that when a carpenter dropped his ax there, it took seven years for it to reach the bottom...
Another legend reported by the Aggadah tells that one day, the Ziz had dropped one of its enormous eggs on Earth, either because it was rotten or because it was infertile. When it crashed to the ground, the object destroyed 300 cedars, and its fluids flooded 60 cities. It is therefore very likely that the creature is a female, but nothing is explained about the location of its nest, nor about a potential mate, nor about the fate of the fertile eggs. It is also said that its wingspan is so great that its wings can hide the sun, and "protect the Earth from storms from the South." And like Behemoth and Leviathan, it will be put to death at the Last Judgment, and its meat of many flavors will be served to the righteous ; however, before that, it will not take part in the fight between its two “cousins”.
The Ziz has been compared to the Rokh of Arabian legends, as well as the Simurgh of Persian mythology, known for its wisdom, and the fact that it witnessed several cosmic cycles. But since the legend of this bird as high as the earth's atmosphere was undoubtedly transmitted orally long before being recorded in the Talmud, it remains difficult to determine who inspired whom.