The Letter to the Philippians is the sole surviving work of the early Christian bishop and martyr, Polycarp of Smyrna. Ever since the 17th century scholars have contested the authenticity and unity of the letter without reaching a settlement. However, new linguistic evidence allows for a reassessment of the controversy. The future participle at Pol. Phil. XIII.1 is one of a mere four occurrences of FPs in the entire corpus of the Apostolic Fathers, and the use of the FP is exceedingly rare among lowregister Judeo-Christian texts in general. The statistical analysis over a wide range of Ancient Greek literary texts conducted in this paper lends support to the conclusion that Pol. Phil. is a uniform text with a spurious interpolation in the form of the bulk of chapter XIII.