What the texts say. Amos promises that God will raise up the fallen tabernacle of David. The Hebrew continues: “that they may possess the remnant of Edom, and of all the heathen, which are called by my name” (KJV). The Septuagint reads: “that the remnant of men, and all the Gentiles upon whom my name is called, may earnestly seek me” (Brenton). In Acts 15, when the apostles and elders debate whether Gentile believers must be circumcised, James quotes Amos in the Greek form, adding “the Lord” as the one sought: “that the residue of men might seek after the Lord, and all the Gentiles, upon whom my name is called.”
How the difference arose. Two small differences in the Hebrew letters produce the two meanings. “Possess” is written yyrshw; “seek” would be ydrshw, differing by a single letter (dalet in place of the second yod). “Edom” is written ’dwm; “man” or “mankind” is ’dm, the same consonants without the vowel letter. The Greek translator either read a slightly different Hebrew text or understood the letters of a text like ours in another way (Strong that the readings are related this way; Debated which happened). W. Edward Glenny’s study of the Septuagint of Amos concludes that the Hebrew text the translator used could have been very close to the Masoretic text, and often resolved difficult or ambiguous passages by interpretation, with a marked interest in the Gentiles seeking the Lord.
Does James’s argument depend on the Greek? Less than it might seem. Even the Hebrew speaks of “all the nations which are called by my name,” that is, nations that belong to the Lord. But the Greek makes the point explicit, and James, as St Luke reports his speech, quotes it in that form. The NET Bible notes that James cites the Greek version that Gentiles would use. The Council’s decision rests also on what God had done: Peter’s report that God had given the Spirit to the Gentiles (Acts 15:7–11, 14).
What the Orthodox Church reads. The Orthodox Church reads Amos in the Septuagint, so Amos and Acts agree. The Church sees here one of the clearest cases where the apostles themselves read the Old Testament in Greek and found in it God’s purpose to gather the nations into the one Church.
How translations handle it. Translations of Amos from the Hebrew, Protestant and Catholic, read “the remnant of Edom”: the KJV, the JPS 1917, the Douay-Rheims (from the Vulgate) and the Reina-Valera 1909 (“el resto de Idumea”). In Acts they all read “the residue of men” or its equivalent, following the Greek of Acts.
What it does and does not change. The inclusion of the Gentiles does not hang on this one verse; it runs through the prophets and the Gospel. The variant does show that the apostles used the Greek Old Testament as Scripture, and that its wording could shape apostolic teaching.