One of the classic arguments used in fundamental theology is the scriptural argument. It aims at showing that in the historical person of Jesus of Nazareth the messianic prophecies and salvific promises of the Old Testament were fulfilled. For this reason, it is also sometimes called biblical or prophetic. An important background, without which it is impossible to properly refer to this argument, is the complex historical and theological reality in which the gradual divergence of the ways of the Church and the Synagogue took place. Of key importance here is the capture and destruction of Jerusalem in 70 CE and the subsequent rabbinic reorganization of biblical Judaism. The primary purpose of this paper is to point out the prominent features of this reorganization and its significance for the formulation of the scriptural argument in fundamental theology. This issue has not yet been widely debated in the literature on the subject. In pursuit of the stated aim, the consequences of the destruction of Jerusalem have been pointed out first. Next, the author discusses the meaning of the Septuagint (LXX) and the fact of its rejection by rabbinic Judaism, and points to the specificity of the Masoretic vocalization of the text of the Hebrew Bible. The final section points to the important inspirations for fundamental theology that flow from the contents discussed. In this way the scriptural argument gains in its significance and can still be helpful in substantiating the person and work of Jesus of Nazareth.