A Lack Of Evidence For The Papacy In Rome During The First Century

"It seems as if at the time of the Epistle [to the Romans] there was no centralized organization, but rather as if there were various small groups of believers. Five such groups seem discernible in the chapter (vss. 5, 10, 11, 14, 15). Note that Paul does not address the Epistle to "the Church at Rome" (cf. 1 Cor. 1:1; 2 Cor. 1:1; Gal. 1:2; 1 Thess. 1:1; 2 Thess. 1:1), but simply to "all who are in Rome, beloved of God, called to be saints" (1:7). The apparent ignorance regarding the Christian movement on the part of the delegates who called on Paul at Rome may be due to the fact that the believers in that city had not yet come into definite conflict with the synagogue (Acts 28:22). At any rate, we believe that the origin of Christianity in Rome must be sought primarily in the work of the converts that came to the city from various parts of the empire."

Henry Clarence Thiessen, Introduction to the New Testament, p. 223