聖書には、ジズについての言及はほんの少ししかない。詩篇50:11には「わたしは山のすべての鳥を知り、Zīz śāday(וְזִיז שָׂדַי)はわたしのもの」とあり、詩篇80.11には、「森から来た猪がそれを荒らし、Zīz śādayがそれを食べる。」とある。これらは翻訳でしばしば失われ、ほとんどの英訳では曖昧な「''獣''」として呼ばれ、特異でも鳥でもないものとして言及されている<ref name=Wazana />。ユダヤ教のアガドーは、ジズについてこう言っている<ref>アガドー(Aggadah)とは、ユダヤ教の古典ラビ文学、特にタルムードとミドラシュに出て来る非法律上の説話である。一般に、アガドーは、民話、歴史的逸話、道徳的勧告、ビジネスから医療まで様々な領域での実用的なアドバイスが盛り込まれたラビのテキストの大要である。(Wikipedia:[https://en.wikipedia.org/wiki/Aggadah Aggadah]より)</ref>。
<bockquote>リヴァイアサンが魚類の王であるように、ジズは鳥類の支配者に任命された。</bockquote>
{{quote|As [[Leviathan]] is the king of fishes, so the Ziz is appointed to rule over the birds. His name comes from the variety of tastes his flesh has; it tastes like this, ''zeh'', and like that, ''zeh''. The Ziz is as monstrous of size as Leviathan himself. His ankles rest on the earth, and his head reaches to the very sky.
It once happened that travelers on a vessel noticed a bird. As he stood in the water, it merely covered his feet, and his head knocked against the sky. The onlookers thought the water could not have any depth at that point, and they prepared to take a bath there. A heavenly voice warned them: "Alight not here! Once a carpenter's axe slipped from his hand at this spot, and it took it seven years to touch bottom." The bird the travelers saw was none other than the Ziz. His wings are so huge that unfurled they darken the sun. They protect the earth against the storms of the south; without their aid the earth would not be able to resist the winds blowing thence. Once an egg of the Ziz fell to the ground and broke. The fluid from it flooded sixty cities, and the shock crushed three hundred cedars. Fortunately such accidents do not occur frequently. As a rule the bird lets her eggs slide gently into her nest. This one mishap was because the egg was rotten, and the bird cast it away carelessly.