Many monotheist traditions appeal to the singularity and power of the sun as a sign of the existence of a single, supreme deity. Akhenaton in Egypt declared the sun god to be the one god Aton. Plato’s crypto-monotheism uses the sun to illustrate the pinnacle of knowledge and wisdom in the Allegory of the Cave. In Zoroastrianism, prayers to the god Ahura Mazda are said to be in the presence of the sun. In the Hebrew Scriptures, God is described as “a sun and shield” (Psalm 84:11) and promises to replace the sun as a source of light when he comes to be with his people (Isaiah 60:19-20). In the Christian New Testament, the transfigured Jesus’ face “shone like the sun” (Matthew 17:2) and the new heaven is promised to be lit by God instead of the sun (Revelation 21:23, 22:5).
Yet it is by no means a given that a planet like Earth should find itself orbiting a single star, and thus giving it a single sun. A great many stars are part of multiple star systems, with two or more stars serving as suns to any planets in the system. For example, the planet Tatooine in the Star Wars franchise and the entire universe of the Firefly franchise exist in a multiple star system, in which multiple suns are visible. Perhaps if humanity had arisen on a planet with two suns, monotheism might not have appeared to be such a readily viable option. The Jawa people of Tatooine, living with two suns, would hardly have the sense of a single life-giving source of light and energy that we get from our single sun, and that quite likely has shaped the development of monotheism.