This study examines the parallels between different systems reported as Valentinian protological and cosmological myths in the cross-examination of church writers and modern authors. Valentinus is considered by most researchers and historians to have been a gnostic teacher from Egypt, teaching in Rome around 160 A.D. The main problem in understanding his system is that not much of his actual writing is preserved. Another issue that arises is the generalization of his teaching by some of the early researchers of the topic, who merged the ideas of Valentinus and his sequential followers into one coherent system or mythology, which brims with a mixture of different ideas, but also time periods. Furthermore, the main zeal of this study is not to determine whether Valentinian was gnostic or not, or if this was the case with his followers and students. The study does not dwell on the history and nature of the Gnosticism of gnosis. Those terms are used ambiguously, bearing in mind the debates over the years, and are briefly acknowledged in the introduction of the study while describing the status quo of the current research. This study advances three theses based on which the research is carried out: T1. In a modern interpretation, Valentinian protology can be understood as the immanent life within a deity with its attributes. T2. Valentinian School was active within Christian communities and members of the Valentinian School grew in knowledge and understanding of the world through various scriptures (in terms of science). The best example of this is Ptolemy's Letter to Flora. T3. The influence of psychology, sociology, archaeology, and other sciences has made it difficult to understand the concepts and customs used by members of "classical" Gnosticism. To unravel the original Valentinian system and distinguish it from its followers, the study in the first chapter, after describing Valentinus’s life, considers various fragments that are ascribed to Valentinus. Those fragments are found in the writings of Hippolytus, Marcellus of Ancyra, and Clement of Alexandria. The fragments are presented in their original form (language) and translated into Croatian. Modern authors, such as Layton and Markschies, and their views of the fragments are then presented and ascribed to each fragment, which serves as an overview of the current research. In the interest of this study, Layton’s assortment of the fragments was given priority over the “classical” Völker's numerical separation of the fragments.1 A key place was given to the hymn Summer harvest. Likewise, another important text was the protological myth from The Gospel of Truth, which is now almost traditionally ascribed to Valentinus. The main ideas found in those reports, Gospel of Truth, and the fragments served as a guideline in the assessment of all other Valentinian systems described by church authors. That led to the shift in focus in the second chapter to the system described by Ireneaus in Against the heresies (AH) I, 11, 1. That system became the cornerstone for viewing all other systems described. It shed new light on the research and understanding of a sort of evolution of the protological system. The first chapter ends with an overview of the most prominent Valentinian teachers and a reference to look for more substantial information on the school and Valentinians in general in the Spiritual Seed by Einar Thomassen. In the second chapter, the focus shifts to Irenaeus’ and Hippolytus’ reports and their description of various systems. Before the main presentation of systems A and B, the way they are usually described, a portion of the chapter is dedicated to an overview of the various systems described by Irenaeus, all of which are ascribed to Valentinian providence. As mentioned beforehand, the most prominent system described is AH I, 11, 1. After a general protological and cosmological analysis of the system, it is compared with Valentinian fragments from the previous chapter. At the end of the analysis of AH I, 11, 1, the protological myth is briefly compared with the system found in Excerpta ex Theodoto, allocated in the writings of Clement of Alexandria.2 What follows are five other reports that Irenaeus describes in his AH. Each system is briefly analyzed and described in its cosmological and protological components insofar as possible since some of them lack in the research of topic segments, especially in relation to everything that was already presented up to this point. Protology is not the focus for some of them. The Great report (AH I, 1, 1. – 8, 5) is the most famous report of the Valentinian system, presented by Irenaeus and labeled by most scholars as system A. In this research, it is ascribed to the Valentinian follower Ptolemy, rather than to Valentinus himself. At the same time, some parts of the reports are omitted since they are not in strict correlation with the research of protology and cosmology, but rather with anthropology. The system is divided into two parts: those concerning and describing the events inside of the Pleroma and those that followed the separation and restoration of Sofia. Those events and reports were there analyzed in the relation to AH I, 11, 1, as well as to the event in Hippolytus’s description of the events, which were also separated twofold. Those events in Hippolytus’s description are usually referred to by scholars as system B. In the conclusion of this research, I argue against that simple classification of the systems since it was shown that other systems should also be considered when thinking in the brackets of the inner and outer life of Pleroma. Therefore, it was proposed that the system in AH I, 11, 1 should be labeled the 1st system or system A. In that regard, the system in AH I, 1, 1 – 8,5 should be labeled the 2nd system or B, the system in Hippolytus’ Refutatio chapter 6 system C and so forth, up to the letter E, the system of a Valentinian named Marcus, also described in AH. System D would be from the Valentinian Doctrinal Letter which is found in the Panairon of Ehiphanius of Salmis, to whom a grave deal was given by Chiapparini in his research Il dvino senza veli and which certainly presents a new take on the Valentinian protology. The third chapter focuses on three modern scholars: Thomassen, Dundenberg, and Chiapparini. The first two are specific in their research of Valentinian schools, more specifically protology, because the root of their research texts is found in the Nag Hammadi library rather than in the reports of church writers. Chiapparini, on the other hand, not only takes into consideration church writers but goes even further and analyses the texts, bringing a new perception of the ancient and modern puzzles. In the conclusion, all aspects of this research are taken into consideration. They are analyzed in the overview of the three main research theses. Aside from new system labels, it is concluded that all the texts, analyses, as well as arguments presented in this research are just an incentive for further studies. To research Valentinus in this sense, it is not enough to take only a part of the system, or a particular idea found in some text to make a proper analysis. Instead, a study like this one is needed to provide a foundation. Each of the analyzed texts requires and deserves an even more detailed examination, as well as broader comparisons with other texts from the period. Primarily, this refers to the analysis of the Gospel of Philip, Excerpta ex Theodoto and Valentinus’s exposition. Most of the topics found in these texts and reports can be used for additional scientific research or even a Ph.D. study. This research is the first original work on Gnosticism in these parts of the world, especially in Croatia. It should be also mentioned that, in terms of the research of Valentinus and his school, some aspects are still in their infancy. This is the third research in the world that focused only on the protology and cosmology of Valentinus, and maybe even the first one that analyzed the texts in between themselves, without aspects other than immanent life in Godhead. That is why it is important to consider AH I, 11, 1 the central theme in this research, together with the mentioned theses and Valentinian fragments. This study contributed to a comprehensive approach to research, connecting and analyzing different views on Valentinian systems, as well as providing the foundations needed for further research. Finally, the research shows that for a deeper understanding of the problem, it is necessary to consider all available descriptions of protological systems and view them from the perspective of the immanent divine, Godhead life. This aspect provides new links between systems and better demonstrates their historical development and continuity that are easily overlooked.