Exegesis:

aphes autois ‘forgive them.’ For the concept of forgiveness cf. on 1.77, autois may refer to the Jewish high priests or to the Roman soldiers. The latter is preferable.

ou gar oidasin ti poiousin ‘for they do not know what they are doing.’ oida means here ‘to realize,’ ‘to understand.’ poiousin refers to what they are doing there and then, not what they usually do.

diamerizomenoi … ta himatia auto ‘dividing (among themselves) his clothes.’ For diamerizō cf. on 11.17.

ebalon klēron ‘they cast lots.’ klēros 1. The semantic relationship between diamerizomenoi and ebalon klēron is that the latter denotes the way in which the former is accomplished, cf. New English Bible. klēros.

Translation:

And, preferably, ‘but,’ i.e. in contrast to what the soldiers did.

They cast lots to divide his garments, i.e. “they parcelled out his clothing and cast lots for the shares” (The Four Gospels – a New Translation), or, to bring out the instrumental relationship, ‘they/the soldiers divided his clothes by casting lots (amongst themselves).’ For to cast lots cf. on “by lot” in 1.9. Some versions use a term with the pejorative connotation of gambling here, e.g. “to throw dice” (Good News Translation), ‘to do like spinning acorns’ (Ekari), ‘to cast-hollow-bamboo-chips’ (Toraja-Sa’dan), but another term in 1.9 and Acts 1.26. For garments see on 5.36.

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.