Among the Fathers of the Church represented in the MS Vat. gr. 666 (12th century), f. 1v, as sources of the Panoplia dogmatica, a collection composed by Euthymios Zigabenos before 1114, John of Damascus arrives tenth and last. His 'Expositio de fide orthodoxa' is, however, one of the texts that provides the greatest mass of material to this polemical compilation. How does Euthymius use the Damascenian œuvre? And what does this imply for the status and consideration of John of Damascus, as a result of this treatment? These are the two issues that the presentation aims to address.