The extensive list of quotations from early Church fathers which apparently support the belief that Jesus is God is impressive even though it is just a cut and paste from this article. For such a high christology to emerge so early in the writings of the Church fathers does require us to ask how reliable these citations are and whether there is evidence of later interpolation after the creeds of the fourth and fifth centuries.
Polycarp's Letter to the Phillipians, 12:2
J. B. Lightfoot writes in the Apostolic Fathers (2.1.546-551; 2.3.316-318) that chapters 10-14 are in no Greek manuscripts but are dependent on a Latin translation which is very loose at times, and paraphrastic. There are also some scattered Syriac quotations, none earlier than the fifth century.
As far as the quotation ("our Lord and God Jesus Christ") is concerned, many manuscripts omit the words "and God" in the phrase.