It is quite legitimate to question how much the named cosenders in either of these examples actually contributed to the letter. Other than these two scenarios, the practice of named cosenders seems quite rare. Atticus wrote one letter together with others.6 Among the extant ancient letter collections, Cicero, Seneca and Pliny wrote none. Among the 645 private letters from Oxyrhynchus, Tebtunis and Zenon listed by Kim,7 I found six.8 Yet none of these letters is even remotely analogous to Paul’s letters.
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