Exegesis:

tou dounai hēmin … latreuein autō ‘to give us … to worship him.’ tou dounai is articular infinitive (cf. Moule 128f) and may be understood to indicate the content of the oath (‘an oath to the effect that …’) or to explain the purpose of God’s dealing as described in vv. 68-73; the former seems to be preferable.

latreuō ‘to serve,’ refers here to worship and adoration of God in general; the spirit or attitude in which this serving of God is performed is indicated by the phrase which follows latreuein, see below.

aphobōs ‘fearlessly,’ goes with latreuein and the subsequent phrase ek cheiros echthrōn rusthentas explains why this fearless service is possible.

ek cheiros echthrōn rusthentas ‘delivered from the hand of the enemies’; rusthentas (in acc.) is attributive to hēmin (in dative).

ruomai ‘to rescue,’ ‘to save,’ ‘to deliver.’ Here the word refers back to lutrōsis (v. 68) and sōtērian (v. 71) but the fact that it is syntactically subordinated to latreuein, shows that the deliverance from the enemies is no end in itself but serves to make possible the service of God as described in the next verse.

(V. 75) en hosiotēti kai dikaiosunē enōpion autou ‘in holiness and righteousness before him.’

hosiotēs occurs in the New Testament always together with dikaiosunē. The two nouns (both †) denote the right attitude towards God and towards man.

enōpion autou ‘before him,’ going either with latreuein (cf. Plummer, New English Bible, An American Translation) or with en hosiotēti kai dikaiosunē (cf. Lagrange, Klostermann), preferably the latter.

Translation:

The syntactic structure of these verses may have to be reorganized, shifting to co-ordination, and/or to direct discourse (as done e.g. in South Bolivian Quechua, Marathi, Kituba). The latter requires in some cases an introductory expression, e.g. ‘saying,’ ‘which is this’ (Marathi), and always changes in the references to the speaker (i.e. God) and the persons spoken of (i.e. Zechariah and his Jewish contemporaries, and in wider perspective the people of Israel in general, viewed as Abraham’s descendants). This may result in something like, ‘I will grant them (or, the people, or, your descendants) that they, delivered from … their enemies, will serve me … before me all the days of their life.’

The following remarks on details assume a rendering in indirect discourse; the renderings discussed can easily be adjusted to a rendering in direct discourse, if required.

To grant us that we, being delivered … might serve him … The introductory phrase, “to grant us”, shows that the situation described in the next clauses is envisaged as brought about by God. In some languages the phrase is transferred to the end of the sentence, .’..; so he/God will grant us’ (cf. Marathi, Kannada); in others the force of the verb is expressed otherwise and embedded in the following clauses, cf. some of the renderings given below. The sentence structure usually has to be reorganized. Some possibilities are: a transposition of the clauses, e.g. ‘that he would allow/enable us to serve him…, after we (or, because we, or, as persons who) have been delivered…’; a change in the pattern of subordination, e.g. ‘(that) he will kindly deliver us…, so-that we can serve him…’ (Balinese); or a shift to co-ordination, e.g. ‘that he will save us from…, and give that we … may be able to worship him’ (Tagalog, similarly Good News Translation), or with a further, lexical shift, ‘that he will enable us to escape … and to serve him…’ (cf. Marathi). — Often the term used for delivered is identical or closely synonymous with the renderings of “redeemed” (cf. references on v. 68) and/or “saved” (cf. on v. 47). — Serve, or, ‘carry-on-the-head,’ i.e. worship (Balinese), ‘cause-(ourselves)-to-be-slaves to’ (Tboli), ‘work for’ (Apache, Medumba).

Without fear, or, ‘fearlessly’ (Marathi), ‘not having a fearful heart’ (Lahu).

V. 75 contains three more qualifications of “serve him”. To avoid too heavy a syntactic structure, one may repeat ‘to serve’ here (Kituba).

In (i.e. with, or, having) holiness and righteousness, or, shifting to a verbal construction, e.g. ‘acting holily and (acting) righteously,’ ‘having-holiness and having-righteousness’ (Batak Toba); or to an adjectival construction, e.g. ‘we … as holy and righteous persons,’ or, ‘pray-to him in worship that is holy and perfect’ (cf. Kituba). For holiness some versions use the word that also renders Gr. hagios ‘holy’ (cf. on v. 15), but a different rendering is preferable, e.g. ‘purity’ (Balinese), ‘perfection (lit. roundness of heart)’ (Tae’ 1933), ‘being-sufficient (i.e. complete, perfect, acceptable)’ (Kituba), ‘unreserved obedience’ (Tboli, using a noun built on the expression ‘his breath/soul is conformed, lit. repeating’). For righteousness before him see on v. 6.

All the days of our life. The more literal “all our days” (The Four Gospels – a New Translation, Phillips), au long de nos jours (Bible de Jérusalem) may be possible in some languages, but more often the phrase must be expanded, e.g. “all the days of our life” (Good News Translation), or changed, “our whole life long” (New English Bible), ‘as long as we live’ (e.g. Javanese), ‘as long as our breath/spirit-of-life comes’ (Tae’), ‘to the end of our lives’ (Lahu), ‘until being short our sprout/shoot,’ i.e. ‘until we die’ (Tboli).

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.