The word translated turn back is not used anywhere else in the New Testament. Of its possible meanings in New Testament or later times, the most appropriate here is “disturbed” (Best), “shaken” (Translator’s New Testament Barclay), “unsettled” (Jerusalem Bible). Die Bibel im heutigen Deutsch interestingly transfers “your faith” from verse 2: “He was to strengthen and encourage you, so that no one should let himself be turned aside from the faith.”
In some languages there may be no meaningful connection between “turning back” and “faith” or “trusting.” Therefore it may be necessary to say “so that none of you would give up believing,” or “… would cease trusting Christ.”
These persecutions (already mentioned in 1.6 and 2.14) must often be rendered as “the way in which you have suffered persecution,” or “the ways in which people have caused you to suffer.”
You yourselves know. Good News Translation follows the Greek closely here in emphasizing you by the addition of yourselves; but the emphasis really attaches to the whole phrase; there is no contrast with any other group of people. Moffatt transfers the emphasis to know: “You know that well” (cf. Knox Die Bibel im heutigen Deutsch). Barclay (cf. Translator’s New Testament) emphasizes both elements: “You yourselves well know.” Bijbel in Gewone Taal, like Moffatt, emphasizes the whole phrase by transferring it to the end of the sentence: “that you know.”
Such persecutions are part of God’s will for us. Good News Translation and Bible en français courant make explicit a reference to God which is implicit in the text, which could be translated almost literally “that is why we have been put here.” Here, as in many places, the passive implies an activity of God. References to “our appointed lot” (New English Bible, cf. Revised Standard Version), like the use of the verb “destined,” wrongly suggest an impersonal fate, which is far from Paul’s way of thinking. The context shows that here “we” includes Paul, his companions, and the Thessalonians. In the next verse, however, the Thessalonians are excluded from “we.”
The rendering of such persecutions are part of God’s will for us must be done with care. Otherwise the reader may think that God himself had purposely planned or even organized the persecutions against the Christians in Thessalonica. In some languages it may be necessary to say “God has permitted these persecutions to come to us,” or “God has allowed these people to cause us to suffer.” It is sometimes possible to speak of “God’s will” as being “God’s plan,” for example, “God’s plan for us includes our being caused to suffer.”
Quoted with permission from Ellingworth, Paul and Nida, Eugene A. A Handbook on Paul’s First Letter to the Thessalonians. (UBS Handbook Series). New York: UBS, 1976. For this and other handbooks for translators see here .