The aim of this work is to analyze the explanation of the biblical commandment that prohibits adultery formulated by Philo of Alexandria in On the Decalogue 121-131 and The special laws III 8-11. We will examine how Philo defines this transgression and what are the motives which justify its interdiction. We will compare his interpretations with the text that functions as an exegetical basis, the Septuagint, and, at the same time, we will try to recognise the links between his thought and the two cultural streams that converge in him, Jewish and Greco-Roman. In this manner, we will be able to understand how Philo’s explanation is placed in its socio-cultural context and what is the originality of his thought in relation to a social behaviour...