A.T. Robertson Commentary Hebrews 1:2

"hath at the end of these days spoken unto us in [his] Son, whom he appointed heir of all things, through whom also he made the worlds;" — Hebrews 1:2 (ASV)

At the end of these days (επ' εσχατου των ημερων τουτων). In contrast with παλα above.

Hath spoken (ελαλησεν). First aorist indicative of λαλεω, the same verb as above, "did speak" in a final and full revelation.

In his Son (εν υιω). In sharp contrast to εν τοις προφηταις. "The Old Testament slopes upward to Christ" (J. R. Sampey). No article or pronoun here with the preposition εν, giving the absolute sense of "Son." Here the idea is not merely what Jesus said, but what he is (Dods), God's Son who reveals the Father (John 1:18). "The revelation was a son-revelation" (Vincent).

Hath appointed (εθηκεν). First aorist (kappa aorist) active of τιθημ, a timeless aorist.

Heir of all things (κληρονομον παντων). See Mr 12:6 for ο κληρονομος in Christ's parable, perhaps an allusion here to this parable (Moffatt). The idea of sonship easily passes into that of heirship (Galatians 4:7; Romans 8:17). See the claim of Christ in Mt 11:27; 28:18 even before the Ascension.

Through whom (δι' ου). The Son as Heir is also the Intermediate Agent (δια) in the work of creation as we have it in Col 1:16f.; John 1:3.

The worlds (τους αιωνας). "The ages" (secula, Vulgate). See 11:3 also where τους αιωνασ=τον κοσμον (the world) or the universe like τα παντα (the all things) in 1:3; Romans 11:36; Colossians 1:16. The original sense of αιων (from αε, always) occurs in Heb 5:20, but here "by metonomy of the container for the contained" (Thayer) for "the worlds" (the universe) as in LXX, Philo, Josephus.