Luke 18:18 New English Translation

¹⁸Now^[a] a certain leader^[b] asked him, “Good teacher, what must I do to inherit eternal life?”^[c]

Luke 18:18 tn Here καί (kai) has been translated as “now” to indicate the transition to a new topic.
Luke 18:18 tn Grk “a certain ruler.” BDAG 140 s.v. ἄρχων 2.a takes this to be a member of the Sanhedrin, but Bock understands this to be “an influential wealthy man or civic leader who may have been known for his piety” (D. L. Bock, Luke [BECNT] 2:1476).sn Only Luke states this man is a leader (cf. the parallels in Matt 19:16-22 and Mark 10:17-22, where the questioner is described only as “someone”). He is probably a civic leader of some kind, a leader in the society.
Luke 18:18 sn The rich man wanted to know what he must do to inherit eternal life, but Jesus had just finished teaching that eternal life was not earned but simply received (18:17). See the similar question about inheriting eternal life in Luke 10:25.

New English Translation (NET)