WantingTruth:
A lot of interesting points that coincide with the discussion here in your linked writeup:
- God telling Jesus at his baptism, "This is my Son . . ." (and later, as in Mt 17:5) ties back to Psalm 2:7. Both Psalm 2 and 110 are regarded as Davidic inauguration psalms. And thus, their application to Jesus has overtones of him having been made king. (See also here.)
- Hebrews 1:1,2
(Hebrews 1:1, 2 NWT) . . .God, who long ago spoke on many occasions and in many ways to our forefathers by means of the prophets, 2 has at the end of these days spoken to us by means of a Son, whom he appointed heir of all things, and through whom he made the systems of things. . .
The NWT greatly softens the impact of what the writer of Hebrews is saying by the rendering, "at the end of these days." (See here for how others render the phrase.) The WT holds to the idea that 1914 marks the start of the "last days."
The NAC-Hebrews commentary (David L. Allen, pp. 102-03) has this to say about "in these last days" (NIV rendering):
The expression "in these last days" contrasts with "in the past" [NIV; "long ago" NWT] of v. 1 and is descriptive of the time when the readers of the epistle lived. The phrase "in these last days" (ep' eschatou ton hemeron) is found in the Septuagint (with various inflections) and translates a Hebrew temporal idiom for the future as distinct from the past. The Jewish perspective of two ages - this age and the coming eshatalogical age - is well known [except among those taught by the WT - Bobcat]. The rabbis debated in which age the Messiah would appear, finding Old Testament evidence both ways. It is probably best to link the two at the appearance of Jesus: the closing out of "this age" and the inauguration of "the coming age." The phrase had come to have a technical eschatalogical significance in Jewish thought, and this was incorporated into the New Testament. The author of Hebrews, like the other New Testament writers, viewed the life, death, resurrection, and exaltation of Jesus as the inauguration of "the last days." [See two other quoted references that have the same idea here. - Bobcat] The present time in which the readers [of Hebrews] are living is "the last days" in contrast to the palai ["long ago" NWT - Bobcat] of v. 1. It is not only that the appearance of Jesus occurred during the last days, but that his appearance initiated the last days.
Also concerning the NWT rendering "at the end of these days," a footnote in the commentary says:
Lunemann (Hebrews, 393) correctly noted that ton hemeron touton [literally "the days these" - Bobcat] should not be taken in apposition to ep eschaton with the meaning "at the period's close" ["at the end of these days" NWT - Bobcat], which these days form.
The NIGTC-Hebrews commentary (Paul Ellingworth, p. 93) also comments about "in these last days":
. . . [the phrase] is Septuagintal, used in echatalogical contexts such as Numbers 24:14 and Daniel 10:14 LXX, pasages which have other points of contact with Hebrews. Esxatou ["last"] is neuter, meaning not "on the last of the days," but "in the last days," or more idiomatically "in the end time." . . . Hebrews distinctive (not Septuagintal) addition of toutwn ["these"] indicates that the last days have begun. Toutwn should be taken with the whole phrase: "in these days which are the last days," not "at the end of these days."
It appears to me that the NWT rendering, "at the end of these days," is likely motivated by existing WT doctrine about "the last days."
I have some other comments in line with your writeup, but will stop here for the sake of brevity.
Take Care