While the approach of the classical philosophy draws attention to the things that exist and to the entities we can discern, the contemporary philosophy tends to emphasise the absence of the being and the impossibility to cognise it. Therefore, the classic theory can fully confirm that potius est esse quam non-esse, yet nowadays it seems that the opposite is true: potius est non-esse quam esse. It appears, we would miss one transcendental characteristic of the being, the one which refers to the opposite of the being, to what is not yet known, or in extreme case, does not exist, namely, the transcendental character of the “mystery”. This article presents the being as a mystery and the bipolar structure of all the beings created by God. This allows to indicate the consequences of such understanding of the being, especially for the relationship between philosophy and theology. For this purpose, the paper has been divided into three parts. First, we clarify what is meant by the being as a mystery. Then, knowing that being refers to the truth, we analyse the relationship between the truth and the mystery. Finally, we are able to describe the human vocation to participate in the mystery and we may perceive the faith, the prayer and the liturgy as the three ways to enter the mystery and to open ourselves to the knowledge of the truth.