Classical secularization theories have been subject to criticisms for their inability to explain religious change and vividness in modern society. The theory of existential security claims to respond to such criticisms. Indeed, unlike conventional theories, the theory of existential security asserts that the principal catalyzer for secularization is not rationalization and differentiation, but security. Accordingly, it explains secularity and religious vividness in a global aspect. Therefore, this paper questions the foregoing claims of existential security theory, since the latter cannot be different from conventional theories because of their common growth and the context in which they were developed. In addition, this study argues the difficulty of considering a single perspective to explain religiosity in a global aspect. Accordingly, the paper critically addresses the theory of existential security in light of sociological data and analyses.