Many languages distinguish between inclusive and exclusive first-person plural pronouns (“we”). (Click or tap here to see more details)
The inclusive “we” specifically includes the addressee (“you and I and possibly others”), while the exclusive “we” specifically excludes the addressee (“he/she/they and I, but not you”). This grammatical distinction is called “clusivity.” While Semitic languages such as Hebrew or most Indo-European languages such as Greek or English do not make that distinction, translators of languages with that distinction have to make a choice every time they encounter “we” or a form thereof (in English: “we,” “our,” or “us”).
For the first part of the verse (“our Lord Jesus Christ” and “our gathering” in English translations), translators typically select the inclusive form (including the addressee), for the second part (“we ask you” in English translations), translators typically select the exclusive form (excluding the addressee).
Source: Velma Pickett and Florence Cowan in Notes on Translation January 1962, p. 1ff.
In Fijian, the paucal exclusive form keitou (“of me and a few [two or slight more]”) is used for the second part. This choice is understandable in view of the introduction found in both letters to the Thessalonians, where the writer Paul indicates clearly that the letters were co-authored by two other colleagues, Silas and Timothy, hence the use of a pronoun referring to three people (“Paul, Silas and Timothy”).
Source: Joseph Hong in The Bible Translator 1994, p. 419ff.