Exegesis:

ouk elēlutha ‘I have not come’ with following final infinitive, implying the sense of a mission.

dikaious alla hamartōlous eis metanoian ‘to call righteous but sinners to repentance.’ dikaious and hamartōlous correspond to hugiainontes and kakōs echontes respectively, in v. 31, but further application to one of the groups of the moment, i.e. Pharisees and tax collectors, is omitted deliberately.

eis metanoian (cf. on 3.3) ‘to repentance’ goes with kalesai and indicates the purpose of the calling (cf. Phillips, Willibrord). Syntactically the latter has both dikaious and hamartōlous as its objects, but since righteous people do not need to repent, it refers semantically only to hamartōlous.

Translation:

The sentence structure may have to be changed and/or the ellipsis to be filled out, e.g. ‘I have come to call sinners to repent, not (come to call) the righteous (to repent).’

Call is used here in the sense of ‘to summon to a particular activity’; it does not refer to loudness of voice.

The righteous, see references on 1.6; in Navajo the term has to be described, ‘those who say, “I don’t do evil” ’; the specific connotation the word has brought out in Good News Translation‘s ‘respectable people’ (contrasting with ‘outcasts’ for ‘sinners’).

To repentance, often better as a verbal phrase, ‘to (or, in order that they) repent.’

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.