"There was a time when the life of men was unordered, bestial and the slave of force, when there was no reward for the virtuous and no punishment for the wicked. Then, I think, men devised retributory laws, in order that Justice might be dictator and have arrogance as its slave, and if anyone sinned, he was punished. Then, when the laws forbade them to commit open crimes of violence, and they began to do them in secret, a wise and clever man invented fear (of the gods) for mortals, that there might be some means of frightening the wicked, even if they do anything or say or think it in secret. Hence, he introduced the Divine, saying that there is a God flourishing with immortal life, hearing and seeing with his mind, and thinking of everything and caring about these things, and having divine nature, who will hear everything said among mortals, and will be able to see all that is done. And even if you plan anything evil in secret, you will not escape the gods in this; for they have surpassing intelligence. In saying these words, he introduced the pleasantest of teachings, covering up the truth with a false theory; and he said that the gods dwelt there where he could most frighten men by saying it, whence he knew that fears exist for mortals and rewards for the hard life: in the upper periphery, where they saw lightnings and heard the dread rumblings of thunder, and the starry-faced body of heaven, the beautiful embroidery of Time the skilled craftsman, whence come forth the bright mass of the sun, and the wet shower upon the earth. With such fears did he surround mankind, through which he well established the deity with his argument, and in a fitting place, and quenched lawlessness among me ... Thus, I think, for the first time did someone persuade mortals to believe in a race of deities."
Critias (455-403 BC), "Sysiphus"