"theological differences in Corinth: there weren't any"

Richards and O' Brien:

Paul begins his first letter to the Corinthians with a plea for unity."I appeal to you, brothers and sisters, . . .” he writes, “that all of you agree with one another ..and that there be no divisions among you, but that you be perfectly united in word and thought."  (1 Cor 1:10)  We might ask ourselves what caused the divisions in Corinth. A ll we know is what Paul tells us: “One of you says, 'I follow Paul'; another, 'I follow Apollos,  another, 'I follow Cephas,' still another, 'I follow Christ,'" (1 Cor 1:12). What likely goes without being said for us is that the church was divided either  theologically or over devotion to different personalities. These are two common causes of church divisions in the West. We tend to fall out along doctrinal lines or because we are drawn to one one charismatic pastor over another.

It is possible, though that the divisions among churches were not theological. We may be failing to note ethnic markers that Paul sprinkled all over the text. Apollos was noted as an Alexandrian (Egyptian) Jew (Acts 18:24)  They had their own reputation. Paul notes that Peter is called by his Aramaic name, Cephas, suggesting the group that followed him spoke Aramaic and were thus Palestinian Jews. Paul's church had Diaspora Jews but also many ethnic Corinthians, who were quite proud of their status as residents of a Roman colony and enjoyed using Latin.  This may explain why Paul doesn't address any theological differences.  There weren't any. The problem was ethnic division: Aramaic-speaking Jews, Greek-speaking Jews, Romans and Alexandrians. - "Misreading Scripture with Western Eyes" by E. Randolph Richards and Brandon J. O'Brien, p. 66

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