Exegesis:

hoti introduces direct speech here.

kai tais heterais polesin ‘also to the other towns’; emphatic by position. The phrase refers to the other towns of Galilee, or of the whole country, preferably the latter as v. 44 seems to show.

euaggelisasthai me dei tēn basileian tou theou ‘I must preach (the good news of) the kingdom of God.’ For euaggelizomai cf. on 1.19. dei, impersonal verb ‘it is necessary,’ denotes compulsion of some sort.

basileia tou theou ‘kingdom, or, rule of God.’ The phrase has a dynamic and eschatological meaning. The kingdom of God comes (10.9, 11; 17.20), is near (21.31). It is Jesus’ mission to preach this and to call people to surrender to the rule of God.

hoti epi touto apestalēn ‘because for that I was sent,’ cf. on 1.19.

Translation:

I must, cf. on 2.49.

Preach the good news of, or, ‘about,’ or. ‘that’ (with following verbal clause, see below); and cf. on 3.18.

For the kingdom of God (also in 6.20; 7.28; 8.1, 10; 9.2, 11, 27, 60, 62; 10.9, 11; 11.20; 13.18, 20, 28; 14.15; 16.16; 17.20f; 18.16f, 24f, 29; 19.11; 21.31; 22.16, 18; 23.51). Generally speaking renderings can best be modelled on a phrase such as, ‘God’s being king/chief/ruler,’ ‘God’s rule/government,’ or a corresponding verbal clause introduced by ‘(the fact) that,’ ‘(the time) when,’ ‘(the place) where,’ ‘(the way) how,’ as context requires. If an object is obligatory with the verb, it may be ‘this world,’ ‘men,’ or an appropriate pronoun. In the present verse this leads to ‘news that God will be king/rule (over the world/men).’ For kingdom cf. also on 1.33.

Other cities, i.e. cities distinct from and additional to those that have been mentioned until now, i.e. Capernaum and Nazareth.

I was sent for this purpose, or, “that is what I was sent to do” (An American Translation, New English Bible), ‘it is for this that God sent me,’ or more synthetically, “that is my mission” (Phillips, similarly Sranan Tongo).

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.