Xenophanes

Xenophanes of Colophon, c.570 – c.475 , was a Greek philosopher, poet, and social and religious critic.
Our knowledge of his views comes from fragments of his poetry, surviving as quotations by later Greek writers. To judge from these, his poetry criticized and satirized a wide range of ideas. This included Homer and Hesiod, the belief in the pantheon of anthropomorphic gods and the Greeks' love of athletics and athleticism. He is the earliest Greek poet who claims explicitly to be writing for future generations, creating "fame that will reach all of Greece, and never die while the Greek kind of songs survives".
Philosophy.
Xenophanes' surviving writings display a skepticism that became more commonly expressed during the 4th century BC. He satirized the polytheistic beliefs of earlier Greek poets and of his own contemporaries. "Homer and Hesiod" one fragment states, "have attributed to the gods all sorts of things that are matters of reproach and censure among men: theft, adultery, and mutual deception". Sextus Empiricus reported that such ideas were savored by Christian apologists. Xenophanes is quoted, memorably, in Clement of Alexandria, arguing against the conception of gods as fundamentally anthropomorphic:
But if cattle and horses and lions had handsor could paint with their hands and create works such as men do,horses like horses and cattle like cattlealso would depict the gods' shapes and make their bodiesof such a sort as the form they themselves have...Ethiopians say that their gods are snubnosed and blackThracians that they are pale and red-haired.
Monotheist?
His remark "God is one, supreme among gods and men, and not like mortals in body or in mind". led some to claim he was the first monotheist. Others pointed out that he still referred to other gods.