Scotus is an important figure in the maturation period of medieval Christian theology. In the center of almost all of Scotus's issues, there is also a problem of establishing the relationship between faith and reason, which is the subject of much debate in the Middle Ages. In matters relating to the relationship between reason and will, Scotus's thoughts bear the traces of the Augustinian-Franciscan tradition in many ways. Thus, the moral and religious content of Christianity is more meaningful than the theoretical constructs of belief. Scotus sought to undermine the claim that everything was necessary and unchanging, with a strong theory of logic. In this context, he made a brilliant discovery which he conceptualized as 'simultaneous contingency'. The essence of this contingency theory, which deeply influences the classical Christian conception of Scotus, is based on the understanding that actual reality can be different from what actually is. The theory of contingent reality, in a sense, refers to the liberation of Christian thought from the ancient Greek thought. The essence of the theory of contingency of Scotus is the fact that opposites are possible at the same time. The systematic thought of Scotus is based on the main methodological distinction between the theology of necessity and the theology of contingency. In addition to the compulsory propositions, the knowledge of contingent propositions depends on this doctrine. In addition to the compulsory propositions, the knowledge of contingent propositions depends on this doctrine. In fact, contingent propositions constitute the largest part of theology.