The Potential Meaning of EIS and General Principles of Greek Translation

There are some contexts in which εἰς can be rendered "for," but how we translate this Greek preposition may depend on the aspect/Aktionsart of the verbs used in context and the context of a passage itself. Translating Virgil's Latin work Georgics and Homer's Iliad and Odyssey has taught me the importance of examining how a word (preposition or otherwise) is used in context (a term's usus loquendi). Lexicons are helpful in this regard.

What might be helpful is to look at similar texts/contexts and try to determine what εἰς is most likely to mean in a given setting. Certain examples given in BDAG for "εἰς" (2. beta) seem pertinent for understanding 1 Thessalonians 4:15. Compare Matthew 6:34; 1 Timothy 6:19.