Cf. Acts ii. 9:  Parthians and Medes and Elamites.  These Jewish converts of the day of Pentecost would naturally be the first heralds of the Gospel in their respective countries.  On the dispersion of the Apostles, “Parthia, according to tradition, was allotted to Thomas as his field of labour” (Euseb. Hist. Eccl. III. 1; cf. I. 13).  An earlier notice of the tradition is found in the Clementine Recognitions, L. IX. c. 29, where the Pseudo-Clement professes to have received a letter from “Thomas, who is preaching the Gospel among them.”