A.T. Robertson Commentary Revelation 21:15

"And he that spake with me had for a measure a golden reed to measure the city, and the gates thereof, and the wall thereof." — Revelation 21:15 (ASV)

Had (ειχεν). Regular imperfect here, no longer εχων.

For a measure a golden reed (μετρον καλαμον χρυσουν). See 11:1 for καλαμος (reed). Μετρον is an old word, kin to μητηρ (mother, moulder, manager), an instrument for measuring (μετρεω) as in Mt 7:2, here in the predicate accusative.

To measure (ινα μετρηση). Purpose clause with ινα and the first aorist active subjunctive of μετρεω. The rod of gold was in keeping with the dignity of the service of God (1:12; 5:8; 8:3; 9:13; 15:7).