A.T. Robertson Commentary Luke 20:14

"But when the husbandmen saw him, they reasoned one with another, saying, This is the heir; let us kill him, that the inheritance may be ours." — Luke 20:14 (ASV)

That the inheritance may be ours (ινα ημων γενητα η κληρονομια). That the inheritance may become (γενητα, second aorist middle subjunctive of γινομα). Here Mt 21:39 has σχωμεν "let us get, ingressive aorist active subjunctive." Cf. εχωμεν, present subjunctive of the same verb εχω in Ro 5:1; Mr 12:7 has "and it will be ours" (εστα).