53:3 He was despised and isolated from men, a man of pains and accustomed to illness.  As one from whom we would hide our faces; he was despised, and we had no regard for him.

The Jewish people were so despised by the nations that no one wanted to be near them - their company was shunned by all.  They were chased in exile from one place to another because no one wanted them near.  They were looked upon as less than human and on one even wanted to behold them - they were avoided as if they were plague-stricken.  They Jewish people, indeed, became ill from maltreatment, but received no mercy from their beholders, because they were so despised.
53:4 But in truth, it was our ills that he bore, and our pains that he carried - but we had regarded him diseased, stricken by G-d, and afflicted!
But when the nations will come to realize that falsehoods they believed in, they will attribute Jewish suffering to gentile sins and not to those of the Jewish people.  Instead of seeing the Jewish people as G-d-stricken, they will see them as their scapegoat.
Whereas they once saw them as lacking in human qualities, in wisdom and ethics, they will now see that this character "illness" was not inherent, but imposed by circumstances - the circumstances which they imposed upon them.  And whereas once they tortured them "in G-d's Name," claiming that they are G-d-stricken, now they will admit that the torture was, indeed, all gentile-imposed.
And the Jewish people, indeed, suffer for the world as the heart suffers for the body - whatever illness attacks the body is ultimately borne by the heart.  And as the heart must be kept in the very best shape in order to properly serve the body, the Jewish people must be kept in the spiritually "best shape" - free of sin - so as to properly serve the nations, because the Jewish people are the spiritual heart of the world.
Thus the nations will realize that THEY were the truly sick ones, but it was their heart, the Jewish people, who bore their sins.
53:5 He was pained because of our rebellious sins and oppressed through our iniquities; the chastisement upon him was for our benefit, and through his wounds, we were healed.
Yes, it was our sins, say the nations - it was we who afflicted them.  We were misled by our leaders who told us that we must chastise them to bring ourselves peace.
53:6 We have all strayed like sheep, each of us turning his own way, and Hashem inflicted upon him the iniquity of us all.
All of the earth's nations will then admit how they have strayed from the truth.  Each of them may have gone his own way - Western civilization, Eastern civilization, and within them, each nation unique - but on persecuting the Jewish people they all agreed.  Each of them claimed their relgion was "The Truth," as did each of each religion's countless sects.  But whereas once they all invalidated Jewish faith, they will all now proclaim the falsehood of their former beliefs.  They will proclaim how they all persecuted the Jewish people, following the dictates of their leaders like sheep.  Yet, this will not absolve them of responsibility, for "each one went his own way," acting for his own benefit - to loot the Jewish people of their possessions.  The Jewish people suffered dearly for the nations' sins.
The Mashiach, also, suffers the sins of others, by those among our people who "go their own way" away from Torah and following after the nations religions, which causes Mashiach to tarry in his coming...this is how the "iniquity of us all" is afflicted upon him.

53:7 He was persecuted and afflicted, but he did not open his mouth; like a sheep being led to the slaughter or a ewe that is silent before her shearers, he did not open his mouth.

The Jewish were oppressed bodily, like a lamb being taken to the slaughter.  They were afflicted and fleeced like a ewe by the confiscation of their belongings.  But both things they endured silently, as do the sheep and the ewe.
They also endured the gentiles' religious torments - the "debates" sponsored in the "name of truth."  But whereas the gentiles were backed by government authority and power, the voice of the Jew was silenced even when he proved himself right - who can argue with authority?  This, too, they accepted with silent endurance and went to the stake with faith on their lips.
53:8 Now that he has been released from captivity and judgment, who could have imagined such a generation?  For he had been removed from the land of the living, an affliction upon him that was my people's sin.
Who can speak about what each generation went through in the confinement and judgment of exile?  They were cut off from the "land of the living," the Land of Yisra'el, and tortured by the nations.  The nations claim that the "sins of my people," says Yeshayahu, brought this plague upon them.
But the Jewish people will be taken from the "confinement and judgment" imposed upon them by the kings, the "confined" ones, and the judges:  The kings authorized Jewish persecution and the judges were its executors.  And now they will admit that it was not Jewish sin, but the sins of my nation, each one will say, which brought the exile upon them.
53:9 He submitted himself to his grave like wicked men; and the wealthy [submitted] to his executions, for committing on crime and with no deceit in his mouth.
The Jewish people had always been ready to give up their lives for G-d - to accept whatever devilish "deaths" the powerful "rich and wicked" decreed upon them and to be buried wherever they would be thrown.  Accused of being wicked themselves and of amassing wealth unscrupulously, they were slaughtered mercilessly as the wicked would be slaughtered and their riches looted in their deaths.  Even in death, their graves were desecrated and dug up in search of buried treasures.  But they had done no violence to deserve such a fate, their only "sin" was that they refused to apostatize and speak a faith of "deceit."
53:10 Hashem desired to oppress him and He afflicted him; if his soul would acknowledge guilt, he would see offspring and live long days and the desire of Hashem would succeed in his hand.
Although the Jewish people in exile maintained their faith, they were not free of sin.  So they suffered and were "oppress[ed]" to atone for their sins - it was G-d Who made them afflicted.  Yet, G-d's intention was not to destroy them, only to make them "afflicted." His intention was that they seek Him from their pain and merit to hasten Redemption.  But to do this they must confront their sins, to "consider themselves culpable."  They will then "see offspring" return to the Land and remain there for a "long days" - they will never be exiled again.  All nations, then, will also serve G-d, when the Jewish people's mission, G-d's purpose, will end in success - their mission to proclaim G-d on earth.
53:11 He would see [the purpose] and be satisfied with his soul's distress.  With his knowledge My servant will vindicate the Righteous One to multitudes; it is their iniquities that he will carry.
In the End, the Jewish people will see the meaning of all that they went through -  "[the purpose].....his soul's distress."  They will see how it all was for their refinement and this knowledge will satisfy them.  And with this knowledge, this wisdom, they will teach many nations and bring them all back to G-d.
And the truly righteous among them will see fruit in their misery even while still in exile:  Their faith in the Future allays all pain in the present and satisifies them even now.
But the greatest misery that they suffer in exile is the burden of their own sins - this they "see" and realize themselves.  But despite their own sins, they remained faithful to G-d and that very faith brought deep satisfaction, even though they were materially wanting.  It helped them remain righteous to G-d even when they were burdened with the nations' "sins" - their torture.
The Mashiach, too, will become wise from his suffering and will know the way to lead others to right.  He will show them that way which leads back to G-d and will rectify, "bear," their sins

53:12 Therefore I shall give him a portion with many and he shall split booty with mighty ones.  For he exposed himself to death and let himself be counted among transgressors, whereas he bore the sins of many and prayed for the transgerssors.

Because the Jewish people were always ready for martydom, to "expose themselves to death," because they bore the nations' branding of them as "transgressors" when, in truth, they bore their sins and prayed for them, G-d will return their Land to them, giving them rule over "many" and the booty of "mighty" nations.

MeAm Lo'ez - Yeshayahu