Hebrews 1:1

Heb_1:1-14. The highest of all revelations is given us now in the Son of God, who is greater than the angels, and who, having completed redemption, sits enthroned at God’s right hand.
The writer, though not inscribing his name, was well known to those addressed (Heb_13:19). For proofs of Paul being the author, see my Introduction. In the Pauline method, the statement of subject and the division are put before the discussion; and at the close, the practical follows the doctrinal portion. The ardor of Spirit in this Epistle, as in First John, bursting forth at once into the subject (without prefatory inscription of name and greeting), the more effectively strikes the hearers. The date must have been while the temple was yet standing, before its destruction, a.d. 70; some time before the martyrdom of Peter, who mentions this Epistle of Paul (2Pe_3:15, 2Pe_3:16); at a time when many of the first hearers of the Lord were dead.
at sundry times — Greek, “in many portions.” All was not revealed to each one prophet; but one received one portion of revelation, and another another. To Noah the quarter of the world to which Messiah should belong was revealed; to Abraham, the nation; to Jacob, the tribe; to David and Isaiah, the family; to Micah, the town of nativity; to Daniel, the exact time; to Malachi, the coming of His forerunner, and His second advent; through Jonah, His burial and resurrection; through Isaiah and Hosea, His resurrection. Each only knew in part; but when that which was perfect came in Messiah, that which was in part was done away (1Co_13:12).
in divers manners — for example, internal suggestions, audible voices, the Urim and Thummim, dreams, and visions. “In one way He was seen by Abraham, in another by Moses, in another by Elias, and in another by Micah; Isaiah, Daniel, and Ezekiel, beheld different forms” [Theodoret]. (Compare Num_12:6-8). The Old Testament revelations were fragmentary in substance, and manifold in form; the very multitude of prophets shows that they prophesied only in part. In Christ, the revelation of God is full, not in shifting hues of separated color, but Himself the pure light, uniting in His one person the whole spectrum (Heb_1:3).
spake — the expression usual for a Jew to employ in addressing Jews. So Matthew, a Jew writing especially for Jews, quotes Scripture, not by the formula, “It is written,” but “said,” etc.
in time past — From Malachi, the last of the Old Testament prophets, for four hundred years, there had arisen no prophet, in order that the Son might be the more an object of expectation [Bengel]. As God (the Father) is introduced as having spoken here; so God the Son, Heb_2:3; God the Holy Ghost, Heb_3:7.
the fathers — the Jewish fathers. The Jews of former days (1Co_10:1).
by — Greek, “in.” A mortal king speaks by his ambassador, not (as the King of kings) in his ambassador. The Son is the last and highest manifestation of God (Mat_21:34, Mat_21:37); not merely a measure, as in the prophets, but the fullness of the Spirit of God dwelling in Him bodily (Joh_1:16; Joh_3:34; Col_2:9). Thus he answers the Jewish objection drawn from their prophets. Jesus is the end of all prophecy (Rev_19:10), and of the law of Moses (Joh_1:17; Joh_5:46).