Celsus

According to the Christian father Origen, Celsus (/ˈsɛlsəs/; Greek:Κέλσος) was a 2nd-century Greek philosopher and opponent of Early Christianity. He is known for his literary work, The True Word (also Account, Doctrine or Discourse; Greek: Λόγος Ἀληθής), which survives exclusively in Origen's quotations from it in Contra Celsum. This work, c. 177 is the earliest known comprehensive attack on Christianity.