Exegesis:

epeidēper ‘inasmuch as,’ ‘since,’ implying a reference to something which is already known to the reader, in this case to Theophilus. There is no reason to treat it as a solemn or stately conjunction.

polloi ‘many’ refers to unknown members of the Christian community who have been engaged in writing a Gospel account; that the reference is to writers follows from v. 3.

epecheirēsan ‘have attempted.’

epicheireō ‘to set one’s hand to,’ ‘to attempt.’ The question whether the use of this verb with regard to the work of his predecessors implies a criticism of their work, is much debated. But it should be pointed out (1) that the verb as such is neutral in this respect, and (2) that it was in accordance with Greek literary usage for a writer to refer to work of predecessors in the preface of his own work.

anataxasthai ‘to reproduce,’ or ‘to compile.’

anatassomai either ‘to repeat from memory,’ hence ‘to reproduce’ (Zahn, Moulton-Milligan) or ‘to draw up,’ ‘to compile’ (modern translations). Because of what follows the latter is preferable.

diēgēsin peri tōn peplērophorēmenōn en hēmin pragmatōn ‘an account concerning the things which have been accomplished among us.’

diēgēsis ‘narrative,’ ‘account.’ The use of the preposition peri ‘concerning’ instead of a simple genitive is either due to the literary character of the passage or intentionally somewhat vague because Luke does not want to commit himself as to the completeness of the accounts of his predecessors.

plērophoreō ‘to fill,’ ‘to fulfil,’ or ‘to convince fully.’ Here the participle peplērophorēmenōn admits of two explanations, i.e.: (1) ‘fulfilled,’ i.e. ‘accomplished,’ which means that the events in question “lie now before us a complete whole” (Bruce). Several versions give a rendering which is more general, as e.g. “that have happened” (New English Bible, Phillips), or, “which have taken place” (Williams). The force of the past participle should however be brought out: the “things that have happened” are not described as belonging to the past (which would have been expressed by the aorist) but as something the influence of which is still felt; hence also en hēmin ‘among us’ (see below); (2) ‘fully convinced,’ i.e. “on which there is full conviction among us” (Rengstorf; the most recent edition has “which have been fulfilled”, which belongs to (1)); cf. also Schonfield, “held by us to be fact”. Moffatt‘s “the established facts of our religion” seems to combine both interpretations; An American Translation‘s “the movement which has developed among us” may imply that the preface of the Gospel was intended for both the Gospel and Acts.

en hēmin ‘among us’ but used in a rather broad sense, ‘in our circles,’ ‘in our group as Christians,’ and not denoting the writer and his contemporaries but rather the writer and his fellow Christians.

pragma ‘thing,’ ‘event.’

Translation:

Inasmuch, or ‘because…, as you know,’ or ‘because…, indeed.’ When the casual connection is not expressed here but in v. 3 (see remarks on vv. 1-4), v. 1 should still contain some expression conveying the other idea, e.g. ‘indeed (or ‘as you know’) many people have already tried…’ (Balinese, Kituba).

Have undertaken, or, ‘have lifted the (writing-) brush’ (Chinese Union Version), ‘have-exerted-themselves,’ or, more generically, ‘have begun.’

Compile a narrative of. In languages that have no detailed terminology for stages and genres of literary activity one may say, ‘to gather and (or, in order to) write down,’ or, ‘to write down the full story about.’

Things which have been accomplished among us. The verb may be rendered, ‘have become complete,’ ‘have run their full course’ (Nieuwe Vertaling). The aspect of continuing effect (see Exegesis), if not sufficiently expressed by the form of the verb, or implied in the phrase ‘among us,’ ‘in our midst,’ may have to be indicated by other means, e.g. by adding, ‘and still affect (or, are important for) us,’ hence, ‘the important things that became complete (or, that happened) among us,’ cf. “the momentous happenings in our midst” (The Four Gospels – a New Translation). The other possible interpretation, ‘on which there is full conviction among us,’ results in a clause structure that often has to be simplified, e.g. ‘which have-certainty among us’ (Malay), or recast, e.g. ‘the reality of which is believed among us’ (Balinese); when active forms must be used, it may become, ‘which we know really/truly to have happened,’ taking ‘among us’ as referring to the agents. — Us is usually rendered as exclusive, cf. Exegesis on v. 3. It should be kept in mind, however, that the choice between inclusive and exclusive pronouns is not always dependent only on the question whether the audience is included or not; it may be influenced also by intersecting trends and considerations. Thus in Santali the inclusive pronoun expresses friendly respect (compare the “epistolary we”); similarly in Tae’ common knowledge and interest may induce a speaker to use the inclusive ‘we’ although the person addressed is not in actual fact a member of his group. On the other hand, in languages using honorifics it may be felt impolite to include the speaker and the person addressed in the same group, when the latter’s status is higher than the former’s, as is the case here; this would lead to the use of the exclusive ‘we,’ even if Theophilus is supposed to have been a Christian or catechumen, i.e. a member of the speaker’s group.

Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.