Tolstoy's story sets up a conflict between material desires and human compassion. He uses Ivan's life and death as a way to show the truth that comes with mortality—what we earned in life is not as important as the way we have treated our fellow man. In this way, Tolstoy tells a story very like Charles Dickens's in A Christmas Carol. Unfortunately, though, Ivan has no happy ending like Scrooge, or at least not one where he gets to go out and prove what he has learned. In his final days, Ivan questions how he has spent his life and comes to the conclusion that his priorities were wrong, but it is a dying man's realization only.

The character that foils Ivan and brings about this revelation is Gerasim, his nurse. Gerasim's compassion and dedicated service to Ivan is in contrast to the attitudes of Ivan's other "friends." Gerasim listens to and cares for Ivan the man, not the coworker or the provider. No other character has compassion for Ivan's health. No other character listens to Ivan. This is why they are just "acquaintances." Because no one shows humanity besides Gerasim, no one can be considered a friend.

It's interesting to note that Gerasim is a poor man, which further highlights Tolstoy's theme of the lack of value in material wealth.

Leo Tolstoy's "The Death of Ivan Ilyich" is a story which describes the life and death of Ivan Ilyich. In part one of the text, Ivan's coworkers are told of his death. While many are surprised that a man as young as he has died, many others are far more concerned with the position which will now open up within the company. Readers are shown, through this, that Ivan was not necessarily disliked, but those around him were far more concerned with how they could ultimately benefit from his death.

It seems that many of the people around him were acquaintances and not friends. This is specifically shown when the following line appears:

Fedor Vasilievich and Peter Ivanovich had been his nearest acquaintances. Peter Ivanovich had studied law with Ivan Ilych and had considered himself to be under obligations to him.

This quote illuminates the fact that Ivan did not have any real friends. Instead, he only had acquaintances. Ivanovich only attends Ivan's funeral service in order to try to get his brother in law Ivan's old job. A true friend would not use a funeral to better the individual or his or her family.

Over the course of the funeral, talk is only made of obtaining better employment, financial betterment, and who wants Ivan's old position. Essentially, no one is truly concerned for Ivan or his family. True friends would be.

What is implied by Tolstoy's calling them not friends, but "nearest acquaintances"?

In "The Death of Ivan Ilyich," prior to being sick and near-death, Ivan had only acquaintances, not friends.  Acquaintances are formal, but friends are intimate.  Acquaintances are bothered by death; friends are tolerant.  Acquaintances go through the motions of mourning; friends actually grieve.

Before he dies, he will have made one friend, Gerasim.

Gerasim did it all easily, willingly, simply, and with a good nature that touched Ivan Ilych. Health, strength, and vitality in other people were offensive to him, but Gerasim's strength and vitality did not mortify but soothed him.

AND:

Only Gerasim recognized it and pitied him. And so Ivan Ilych felt at ease only with him.

AND:

Gerasim alone did not lie; everything showed that he alone understood the facts of the case and did not consider it necessary to disguise them, but simply felt sorry for his emaciated and enfeebled master. Once when Ivan Ilych was sending him away he even said straight out: "We shall all of us die, so why should I grudge a little trouble?"

The culture of 19th century czarist Russia was heavily bureaucratic.  To be in society was to be a cog in a machine, to do the same work--day in and day out--with little hope for advancement or reprieve from paperwork and frustration.  As such, Ivan treated his co-workers with detachment and formality.  Private conversations were prohibited.  The society was engineered for efficiency; close relationships were not productive.  This obviously carried over into his marriage and family life, for he took all for granted.

Even his wife and family are acquaintances only.  His wife and relatives and doctor go through the motions of friendship and nursing, but they are not friends or nurses.  They are detached, as he is, even in the rituals of sickness and death.  Ivan is merely something to be tolerated, and they treat him as a kind of sickness, as a dying man, not as a friend, or even a person.

They do not acknowledge him, as Gerasim does, with dignity and respect.  They do not cater to him even when he is ashamed of his condition and does not want to be seen.  Only Gerasim exhibits a kind of primitive Christian charity and unconditional love.   Ironically, Gerasim has not been conditioned by the bureaucracies; as servant of the peasant class, Gerasim has learned to be humble and long-suffering, kind to the sick.  Only he sees Ivan as a human being, not a cog in a machine or a sickness unto death.

In "The Death of Ivan Ilyich," what is implied in Tolstoy's calling the colleagues not friends, but "nearest acquaintances"?

Tolstoy's choice of words in this case illustrates the theme of alienation that is maintained throughout the story. Though Tolstoy is not often considered an existentialist writer, he anticipated the existentialist movement and other modernist trends that were soon to be developed in the literary world.

In spite of the somewhat negative portrayals of Ivan Ilyich's coworkers, probably anyone, even the best of us, who has attended a funeral has experienced the unavoidable awkwardness of these occasions. So to a degree, they should be given a "pass." The overall point, however, that Tolstoy seems to make in the funeral scene and throughout the book is that human beings who are not immediately facing death act as if they are somehow exempt from it. Though death is the one certainty in this world, it's the hardest to accept and to believe in unless we're on the verge of it. Ivan Ilyich is the one person in the novella who has to face this existential issue. The associates, though they, like all of us, have merely been given a temporary reprieve, act as if their exemption from death is somehow a permanent thing. And this shows their remoteness from Ivan Ilyich, their lack of connection to him.

The lack of empathy from his associates during the funeral has an analogue in the behavior of Ivan Ilyich's wife and daughter after he returns from the doctor and begins to tell them what the examination has revealed. They seem uninterested, remote, and are more concerned about the shopping they are about to do. When they leave, Ivan Ilyich is left alone, isolated, to brood about his illness without any support from the family. The doctor, also, when he comes to the house, does not show much of a good bedside manner. Ivan Ilyich has been plunged into a world of isolation in which he must deal with excruciating physical pain, as well as mental suffering, on his own. He finds himself a stranger in his own world.

The isolation becomes complete during his final three days, when Ivan Ilyich is screaming in agony. He is still alive but cut off completely from all the humans on earth, like Jesus during the three days between crucifixion and resurrection. When we look back on his life as it has been shown to us, and sum it up, we must ask, "What was the point of it all?" Tolstoy's answer seems to be that the goal of life is, of course, the endpoint of Ivan Ilyich's journey: death.

In "The Death of Ivan Ilyich," what is implied in Tolstoy's calling the colleagues not friends, but "nearest acquaintances"?

There is a certain irony in this use of the phrase "nearest acquaintances," as actually, the news of the death of their colleague does not produce grief, as we might expect it to, but rather much excitement about who will receive Ivan Ilyich's old position. Note the reaction of his former colleagues to the news of the death of one of their number:

So on receiving the news of Ivan Ilyich's death the first thought of each of the gentlemen in that private room was of the changes and promotions it might occasion among themselves or their acquaintances.

Their overwhelming thought, apart from the possibility of securing a promotion, is the thankfulness of feeling that "it is he who is dead and not I" and then the pain of having to fulfill the "tiresome demands of propriety" by attending Ivan Ilyich's funeral. At one stage the narrator calls these gentlemen the "so-called" friends of Ivan Ilyich, and we can see their insincerity and the way that they, like Ivan Ilyich's family and almost everyone else in this excellent novella, except for Gerasim, ignore the reality and enormity of death and its impact on their own lives.