In this thesis, after a general introduction, we first review some differential geometry to provide the mathematical background needed to derive the key equations in cosmology. Then we consider the Robertson-Walker geometry and its relationship to cosmography, i.e., how one makes measurements in cosmology. We finally connect the Robertson-Walker geometry to Einstein's field equation to obtain so-called cosmological Friedmann-Lemaître models. These models are subsequently studied by means of potential diagrams.

Georges Lemaître is quite unknown in Czech society. Although he was one of the scientists who independently anticipated the expansion of the cosmos and later formulated one of the most important hypotheses of the twentieth century - the hypothesis of the Primavel Atom, generally known as the Big Bang Theory as well as he was the president of The Pontifical Academy of Sciences, there has been published almost nothing about him in the Czech Republic. What was Lemaître's life like? What does his hypothesis mean in the context of Christian astronomical discourse of last centuries? How was his mission of the priest linked with work in astrophysics and mathematics?

The thesis analyzes the thinking, legacy and the second life of the work of a prominent mathematician, cosmologist and the Catholic priest Georges Lemaître. The patterns of his thinking (expecting the intelligibility of the cosmos, assuming the hidden nature of God for research of natural science, seeing indeterminism in the evolution of the cosmos and separating the scientific and religious approach to reality) are presented on the basis of sources and literature based on Lemaître's texts and texts of scholars who dealt with his life and work. Everything is further complemented by the opinions of authors writing about the broader contexts of the history of cosmology and its interferencee with religion. Those long-term tendencies are drawn in more detail and further connected and compared with more general European ideas (the book of nature, the question of human free will, light as a backdrop of creation, appreciating the simplicity of hypotheses). Special emphasis is placed on the religious connotations of Lemaître's thinking - these are also presented with regard to the development of time, to which insights are further applied using modern models of the relationship between science and religion. It is the temporal transformation of that relationship within Lemaître's life path and the resulting...