During the first centuries of our era, a quite remarkable phenomenon took place : many Christian authors used pagan testimonies to exhibit the fundamental dogmas of Christianity – including the uniqueness of God. To better understand this phenomenon, we look at a text which, though variously used as a doxographic source, has, in itself, received little attention from modern research : Chapter 14 of the Fifth Stromateus of Clement of Alexandria, which contains an extremely rich and varied collection of pagan testimonia with monotheistic content, meant to prove the “theft of the Greeks”. In this paper we review the figures of Greek philosophers mobilized by Clement, focusing on the precise content and tenor of the doctrines set out in the texts cited, whether authentic or (sometimes) pseudepigraphic. We also examine how the Christian author integrates these texts and ideas into the apologetic and didactic approach of his work.