The compendium of Augustinus’ De grammatica, though reduced in its present form to a simple textbook, reveals traces of Varro’s model, in particular in the treatment of verbal inflection, divided into three conexiones. The theory of linguistic analogy and of the mathematical structure underlying to the human language, so typical of Varro, are likely to have provided to Augustinus the key to consider also grammar among the tools which are capable of raising man from sensible knowledge to the intelligible world.