BGU 1079

Σαραπίων Ἡρακλείδῃ τῷ
ἡμετέρῳ χα(ίρειν). ἔπεμψά σοι
ἄλλας δύο ἐπιστολάς,
διὰ Νηδύμου μίαν , διὰ
Κρονίου μαχαιροφόρου
μίαν · λοιπὸν οὖν ἔλα-
βον παρὰ το(ῦ) Ἄραβος τὴν
ἐπιστολὴν καὶ ἀνέ-
γνων καὶ ἐλυπήθην.

 This is a much discussed letter BGU IV. 1079 (= CPJ II 152; White, LAL, No. 87; Sel. Pap. I 107; W.Chr. 60) because of the later reference to 'the Jews'. But the opening is interesting for a number of reasons:

1. reference to earlier correspondence often (as here) identifies the letters by their respective carriers: 'I sent two other letters to you, one through Nedymos, one through Kronios the swordsman'.
2. here we find explicit, what I think is implicit in the use of  ἔπεμψά σοι ... διὰ, that is that it refers to the letter carrier.
3. παρὰ is used for receipt of a letter by the agency of a letter carrier: 'Finally, then, I received your letter from the Arab ...' 
4. the received letter is read by the recipient (not by the letter carrier, this never happens!)
5. the author uses  λοιπὸν very early in a much longer letter (cf. 1 Cor 1.16; 7.29; Phil 3.1 - also late in letters: 2 Cor 13.11; Phil 4.8; 2 Thess 3.1; 2 Tim 4.8).