Final answer:
Satan began casting doubt on the Word of God is a concept reflecting on the biblical account of the serpent in Genesis, where Satan deceives Adam and Eve, which is a recurrent theme in Judeo-Christian stories and religious discussions.
Step-by-step explanation:
The assertion that Satan began casting doubt on the Word of God can be sourced to various Bible stories within the Judeo-Christian tradition. In these narratives, the figure of Satan is often represented as the bringer of temptation and falsehood, undermining the commands or truths presented by God. A notable instance is in the Book of Genesis, where Satan, appearing as a serpent, deceives Adam and Eve, leading to their disobedience and the subsequent fall of man.
This theme of questioning divine authority and the resulting moral and existential implications has been explored in various texts and interpretations throughout history. The concept of evil and its origins in relations to deity's plan, as well as the free will of beings created by God, has been a subject of theological debate, as seen in discussions surrounding the nature of Lucifer's rebellion and its impact on the human condition.