In him (en autōi). Repeats the idea of en tōi Christōi of Eph 1:10.
We were made a heritage (eklērōthēmen). First aorist passive of klēroō, an old word, to assign by lot (klēros), to make a klēros or heritage. So in lxx and papyri. Only time in N.T., though prosklēroō once also (Act 17:4).
Purpose (prothesin). Common substantive from protithēmi, a setting before as in Act 11:23; Act 27:13.