As component parts of the one building. The reference is to individual Christians, not to communities.
Habitation (κατοικητήριον)
Answering to temple. Only here and Rev 18:2. Indicating a permanent dwelling. See on dwell, Luk 11:26; see on Act 2:5; see on Mar 5:3. In marked contrast with sojourners, Eph 2:19.
Through the Spirit (ἐν)
Better, as Rev., in. In the fellowship of the indwelling Spirit.