Everyone  must someday have had to make a decision; so, he started thinking about that decision, thus putting before his eyes all the probabilities that may affect the decision. As a result of thinking, the final decision would be based on these accumulative probabilities. The totality of this process of thinking, which begins with amassing the parts and ends with making a final decision, is in mathematics termed as the probability calculation. Before being one of the significant, precise and reason-based mathematical theories that has its own theorists, advocates and laws, the probability calculation theory is initially a traditional and rational theory that people usually use in their ordinary and daily activities, although they, of course, fail to pay attention to its mathematical applications. The current essay is an attempt to make mathematics, represented by this important theory, exceed its ordinary engagement in man’s life affairs and move to the aspect of creed in order to investigate and explore any possibility of employing the probability calculation theory for proving the existence and the unity of the Creator of the universe.