This systematic study studies the evolution of the Greek language. The study focuses on the historical handwriting tradition of our language from the 17th century, until the beginning of the 19th century. It investigates the handwritten grammatical codes of the holy monastery of Ag. Stephanou Meteoron, with numbers 76 and 146, which deal with the historical description of the structure of the language.The research methodology and the historical-interpretive approach were necessary to deepen all information, written and spoken, following the rules and procedures that guide scientific research.The aim was achieved through the analysis and assurance of the validity and reliability of the information obtained from the scientific literature, from sources and handwritten codes. The connection between the Greek language, handwritten codes, “student books-mathimataria” and written language, with the forms it took over the centuries.The findings of the study reveal the greatness of the Greek language, the need to preserve it and the richness of knowledge gained from the study of manuscripts and “mathimataria”. We find that our language is an object that, as you explore it, you discover new aspects and new horizons for learning and studying.Starting from prehistoric times, we have seen that language is one of the greatest achievements of human civilization, because thanks to it, man has developed the language that forms the basis of his civilization.Continuing, we studied the Greek language and its written tradition, as it is of fundamental importance for the world language and culture, since, on one hand, it was used to express the most cultivated and philosophical thinking of the ancient world and on the other hand, because the new Greek language is based on it, but also a number of other languages, such as Latin and other Latin originated languages are based on Greek language as well.In conclusion, what gives the Greek language supremacy is the richness of its vocabulary, the ability to create new words, its accuracy and its literal meaning. It is a language "teacher", with historical continuity, wisdom and musicality. It is a fluent language.This is because our language has the peculiarity of continuing the language of ancient Greeks and as a model in European and modern civilization it has gained universalism. In its present form, properly cultivated, as the mother tongue of the young Greeks, is a worthy instrument of a Modern Greek civilization.In view of the Church's contribution to the preservation of the Greek language, we studied the history, the offer of education and the historical record of the Holy Monastery of St. Stephen Meteor. The valuable manuscript Codes housed in the archives of the monastery are evidence of the efforts of the monks and contributed to the education and cultural rebirth of the underprivileged Greek children during Turkish domination.The study of the two handwriting grammars revealed to us the way in which teaching was made, led us to historical sources, revealed to us that in those difficult times the Greek language survived. We have found that Grammar and, in particular, its handwritten tradition, is our irresistible spiritual advantage. It is the indisputable and actual linguistic richness of three thousand years, concentrated on a number of handwriting grammars, those that have been preserved in public, monastic and private archival collections.