But let us suppose that the 'blessing of Aman' was also accorded to Men. What then? Would a great good be done to them? Their bodies would still come swiftly to full growth. In the seventh part of a year a Man could be born and become full-grown, as swiftly as in Aman a bird would hatch and fly from the nest. But then it would not wither or age but would endure in vigour and in the delight of bodily living. But what of that Man's fëa? Its nature and 'doom' could not be changed, neither by the health of Aman nor by the will of Manwë himself. Yet it is (as the Eldar hold) its nature and doom under the will of Eru that it should not endure Arda for long, but should depart and go elsewhither, returning maybe direct to Eru for another fate or purpose that is beyond the knowledge or guess of the Eldar.

Very soon then the fëa and hröa of a Man in Aman would not be united and at peace, but would be opposed, to the great pain of both. The hröa being in full vigour and joy of life would cling to the fëa, lest its departure should bring death; and against death it would revolt as would a great beast in full life either flee from the hunter or turn savagely upon him. But the fëa would be as it were in prison, becoming ever more weary of all the delights of the hröa, until they were loathsome to it, longing ever more and more to be gone, until even those matters for its thought that it received through the hröa and its senses became meaningless. The Man would not be blessed, but accursed; and he would curse the Valar and Aman and all the things of Arda. And he would not willingly leave Aman, for that would mean rapid death, and he would have to be thrust forth with violence. But if he remained in Aman, what should he come to, ere Arda were at last fulfilled and he found release? Either his fëa would be wholly dominated by the hröa, and he would become more like a beast, though one tormented within. Or else, if his fëa were strong, it would leave the hröa, Then one of two things would happen: either this would be accomplished only in hate, by violence, and the hroa, in full life, would be rent and die in sudden agony; or else the fëa would in loathing and without pity desert the hroa, and it would live on, a witless body, not even a beast but a monster, a very work of Melkor in the midst of Aman, which the Valar themselves would fain destroy

Manwe sends "messengers" to Numenor to attempt to answer the questions. Who are these "messengers"?

Good question. It reminds me of the Istari, but there's no indication that they visited Numenor in the Second Age. I think the messengers were likely members of the Eldar, who for a long time continued to travel back and forth to Numenor. But it's possible that one or more of the Maiar came to Numenor, although not, I think, in bodies of human flesh like the Istari. They could have taken human form, though, or whatever form they chose.

Well, in "Athrabeth Finrod Ah Andreth" (The Debate of Finrod and Andreth), found in Morgoth's Ring, Tolkien implies that perhaps death was a punishment after all, and that originally man was not destined to die. But perhaps that was a late attempt to make his mythology conform to Catholic orthodoxy. The idea of death as a gift is not orthodox Christianity, but it does bear some resemblance to Jesus' promise of everlasting life, which makes devout Christians happy to martyr themselves. The problem is that Tolkien attempts to fit a New Testament idea (everlasting heavenly life after death) into an Old Testament world (no Christ -- yet). When Beren died, Luthien found him in the Halls of Mandos, and I wonder whether all human spirits waited in the Halls of Mandos for Christ to come and release them, so that they could eventually leave the circles of the world. This would look more like the Catholic notion of Purgatory and Limbo.

The Silmarillion, Akallabeth
'...For it is not the land of Manwe that makes its people deathless, but the Deathless that dwell therein have hallowed the land; and there you would but wither and grow weary the soner, as moths in a light too strong and steadfast.'
But the King said: 'And does not Earendil, my forefather, live? Or is he not in the land of Aman?'
To which they answered: 'You know that he has a fate apart, and was adjudged to the Firstborn who die not; yet this also is his doom that he can never return again to mortal lands. Whereas you and your peope are not of the Firstborn, but are mortal Men as Iluvatar made you. ... Nor can the Valar take away the gifts of Iluvatar.

Footnote to Letter 156
This [the idea that taking Aman would confer immortality] was a delusion of course, a Satanic lie. For as emissaries from the Vaar clearly inform him, the Blessed Realm does ot confer imortality. The land is blessed because the Blessed dwell there, not vice versa.

. Do you think this was a wise decision on the part of the Valar? Middle Earth was no place for the Edain at this point and Beleriand, their home was now gone forever. The only mistake the Valar made was making Numenor so close to the Undying Lands, instead of hallowing it out and making it closer to Lindon and the remaining Noldor. It seems however that Manwe and Mandos made the decision, and that Ulmo influenced it - the hand of Eru Illuvatar is there in evidence.

Who are these "messengers"?

Most likely Elves from Eressea, whom the Numenoreans were pretty close with. The Valar would not have sent one of the Noldor or Vanyar, who have little in common with the sea-faring Numenoreans.

do they just mean this type of 'psychological' weariness, or is something more 'spiritual' or 'magical' at work there?

The Undying Lands are just that; nothing ever dies there unless it is killed, and that is unlikely. Mortal Men cannot outlast even the flora over there and will not be able to cope with a place that exudes life unending when they themselves get sick, get hurt, get hungry and so forth.

What do you think of the idea of death as 'leaving the circles of the world' and being a 'gift'?

Men are meant to be free from the cycle of disappointment the Elves in Middle Earth have to live with, seeing the world continually die out, or the monotonous and mundane life in Aman. Eru clearly had something else in mind when He created two Children with varying characteristics.

Seeing death as a gift , as Elros and his heirs did makes it the ultimate comfort- which is why Morgoth didin't just kill Hurin and Turin but tormented them their entire lives to deny them the proper comforts of death. Hurin himself spat in Morgoth's face and said he was going to a place even Morgoth claimed there was nothing.

If you lived for a long time, would you go to death willingly?

The Numenoreans knew when it was time to go, it was when their bodies finally decided to grow old and frail and their minds began to drift into dotage. Aragorn says to Arwen that he doesn't want her having to endure him in an old, feeble state, which must have been pathetic. Tar-Antanamir saw his end coming but refused to accept it, which went against the idea of giving a gift back. A powerful and supposedly wise king is still a fool if he dies as one. If one feels their hundreds of years of life have accomplished much, then their death is not really a bad thing. If one feels like they'd been cheated for hundreds of years, death is not welcome; Elves live forever but tend to accomplish little that lasts compared to Men and Dwarves who live for hundreds- yet Antanamir thinks that he should have his entire lifespan to accomplish something, rather than just handing it over to his son (who ironically got his Sceptre grabbed from him).

Compared to Theoden and Eorl, who died Old and Young respectively and in battle, one can see that the Numenoreans were allowed to live their lives to the fullest and to die in peace without pain. Denethor thought he was going to die but apparently was not, and was clearly not showing signs of it (reflecting old Numenor, in fact). Numenoreans didn't need to chase death or look for it in battle, they could feel it coming and it came slowly to them so they could prepare. I'd say that was an awesome gift if used correctly.

The one exception here is poor Tar-Palantir, who probably died willingly but without hope and happiness- more like "take me now, please", which is really sad.