The main aim of this paper is to demystify biblical cosmogony through Theogenesial Theory as against Darwinism and subsequently elucidate the trichotomous nature of man created by God in His image (Imago Dei). The Theogenesial Theory states that everything came into existence by divine fiat, both the physical and non-physical elements. This theory posits that God is the Source and Beginning of all things—living and non-living things. He created all things. In other words, the universe came into existence as a result of divine fiat. God created the universe through His creative Word by fiat. Life originated through divine creation or divine intelligent design, and not through abiogenesis. All species were created by God, a living Spirit. Theogenesis, according to the Bible, accentuates that God created the universe in six days and rested on the seventh day by speaking it (the universe) into existence. Adopting solus primus scriptura research (SPSR) and a biblical descriptive model, the author develops a Demarcation Standard for Truth (DST) and concludes that Darwinism, or Charles Darwin’s Theory of Evolution, and its associated Big Bang Theory contradict biblical cosmogony. Check Mature Journal and African Journal of Kingdom Education for more articles by the same author African Journal of Kingdom Education in Zenodo African Theologies: A Comparative Analysis of Theogenesial and Theogogical Praxes Between Traditional and Christian Theologies Theogenesial Theory by the same author. Pneumagenesial Theory by the same author. Read About the Author here. Keywords: theogenesial theory, big bang theory, darwinism, origin of the cosmos (universe), tripartite nature of man, cosmogony, science.