ɪn ˈɑːɹɡjuːɪŋ ɐɡˈɛnst pˈoʊp hˈeɪdɹiən ðə lˈaɪbɹi ˈɔːlsoʊ ɐpˈiːld tʊ ɐ lˈɛɾɚ baɪ ɡɹˈɛɡɚɹi ðə ɡɹˈeɪt ɹˈɛdʒɪstɹəm ɹˌoʊmən ɪlˈɛvən. tˈɛn ðæt hæd ˈɑːɹɡjuːd ðæt pˈɪktʃɚz ɑːɹ plˈeɪst ɪn tʃˈɜːtʃᵻz nˌɑːt təbi ɐdˈoːɹd bˌʌt pjˈʊɹli tʊ ɪnstɹˈʌkt ðə mˈaɪndz ʌvðɪ ˈɪɡnɚɹənt.
In arguing against Pope Hadrian the Libri also appealed to a letter by Gregory the Great (Registrum XI. 10) that had argued that Pictures are placed in churches not to be adored but purely to instruct the minds of the ignorant.