sought to interfere, for good, in human matters, and had lost the power for ever.

All of these individuals are guilty as well, guilty—apparently—of failing to help their fellow human beings while they were alive, and now their chains symbolize that guilt.  Marley's chains contain ledgers and cash boxes, indicating the specific ways in which he is guilty of failing humanity; likewise, the ghost here has a chain containing a huge iron safe, which probably indicates that he failed his fellows by hoarding his money rather than helping those in need (like Scrooge, which explains why Scrooge recognizes him).  Since these ghosts are all miserable because they cannot now help the living, it is reasonable to infer that this is what causes their guilt: their failure to help their fellows when they had the chance.  This is why Scrooge's chain would be so much longer and heavier than Marley's; he's had seven more years of denying people help, and seven more years of guilt for it.

Jacob Marley, like his former business partner Scrooge, was exceptionally good at his job. He was an astute businessman with a keen eye for making a profit. Unfortunately, business took over his life to such an extent that he became positively obsessed with making money. For Marley, as for Scrooge, nothing mattered but the bottom line.

As Marley never truly repented for being so greedy and grasping—though on his deathbed he did try to warn Scrooge to change his ways—his ghost has been forced to wander round for all eternity, weighed down with chains consisting of cash-boxes, keys, and heavy purses. All of these items symbolize money, which for Marley was the most important—indeed, the only important—thing in his life.

While he was alive, Marley's soul was weighed down by his obsession with making money. And now that he's dead his unquiet ghost is literally weighed down by the symbols of his earthly obsession. Scrooge needs to take a hint. Just one look at Marley's ghost should tell him that unless he stops being such a greedy old miser then he'll end up the exact same way as his former business partner. Unfortunately, it doesn't, and it will take the visits of three more ghosts to convince Scrooge that he needs to change his ways.

I believe that this question is asking about the symbolism that is present in Jacob Marley's chains. Marley is Scrooge's dead business partner. When his ghost appears before Scrooge in stave 1, Marley is wrapped up with chains and dragging them along with him. They are made of steel, and they are additionally weighted down with various financial objects, such as cash boxes, keys, padlocks, ledgers, deeds, and heavy purses.

Jacob Marley himself tells Scrooge and readers that he is forced to wear the chains in the afterlife.

"I wear the chain I forged in life," replied the Ghost. "I made it link by link, and yard by yard; I girded it on of my own free will, and of my own free will I wore it."

Based on this quote, it appears that ghosts are forced to wear chains that are symbolic of that person's life path and life choices. When Marley was alive, he was quite similar to the Scrooge whom we have already gotten to know by this point in the story: Marley focused on his own wealth. His greed superseded any care that he might have for anybody other than himself. His chains are symbolic of those choices. He put money and finances before people, and now he is forced to walk all of eternity carrying around those choices.

The chains also serve as a way for Marley to try and redeem Scrooge. Marley does not want Scrooge to end up like he does and wander the afterlife similarly weighed down. While Scrooge is hardly transformed at this point in the story, Marley and his chains start Scrooge's transformation.

In Stave I of Charles Dickens' A Christmas Carol, the reader is introduced to the character of Ebenezer Scrooge, a bitter, miserly figure whose priorities -- business first, last, and always -- receive an unexpected reprioritization after he is visited in his bed chamber by a series of ghosts. Scrooge is depicted as "a squeezing, wrenching, grasping, scraping, clutching, covetous, old sinner." Dickens emphasizes, and reemphasizes, that his protagonist is completely lacking in humanity, not even able to offer a positive comment at the funeral of his long-time business partner Jacob Marley. One night, however, upon retiring for the evening, Scrooge is disturbed while sitting before his fireplace in his bed gown, slippers and nightcap. It is the sound of chain being dragged across the floor. Now, Scrooge had already, upon arriving home from another day at the office, been momentarily startled by the image of his now-deceased business partner in the brass knocker on his front door. Now, in the warmth of his home, he is disturbed by a spirit or ghost dragging the chain that must have made the sound that first disturbed Scrooge. Dickens provides the following description of the chain that is being dragged by the ghost of Jacob Marley:

"The chain he drew was clasped about his middle. It was long, and wound about him like a tail; and it was made (for Scrooge observed it closely) of cashboxes, keys, padlocks, ledgers, deeds, and heavy purses wrought in steel."

Note these details: cashboxes, ledgers, deeds, heavy purses. These are the items associated with Scrooge, and his former partner's, business. "Scrooge and Marley" was the accounting business that now rested in the solitary grip of the surviving partner, Ebenezer Scrooge. The "tight-fisted" businessman lived a lonely existence, preferring to keep others at arm's length and content only to make more money while treating his loyal and diligent assistant, Bob Cratchit, like a veritable slave. Now, we move on to the conversation between Marley's ghost and Scrooge, and the symbolic importance of the chain is made even clearer. As Scrooge looks in horror at this apparition, the ghost of Jacob Marley explains the metaphorical meaning of the chain:

“I wear the chain I forged in life,” replied the Ghost. “I made it link by link, and yard by yard; I girded it on of my own free will, and of my own free will I wore it. Is its pattern strange to you?”

What Marley's ghost means, of course, is that Scrooge's long-time business partner has come to recognize in death what he failed to understand in life -- that one's soul is weighed down by the materialism that marginalizes the human contacts that really give meaning to one's life. Marley has come to warn Scrooge that, unless the latter changes his life, he, Scrooge, will similarly be condemned to an eternity of dragging the chain of cashboxes, business ledgers, etc.

In stave 1 of Dickens's classic story A Christmas Carol, Ebenezer Scrooge is visited on Christmas Eve by the ghost of his former business partner, Jacob Marley, who warns Scrooge that he will be visited by three spirits throughout the night. When Marley's ghost appears in Scrooge's chamber, a long chain made from cash-boxes, keys, padlocks, ledgers, and deeds is wrapped around his semi-transparent body. The items attached to the chain symbolically represent Jacob Marley's greed and the material items he valued in life.

When Jacob Marley was alive, he was a notorious money-lender and dedicated every ounce of his energy to accumulating wealth by making shrewd, selfish business deals. Similar to Scrooge, Jacob Marley was a callous, insensitive man who was only concerned with his money. Marley's ghost proceeds to tell Scrooge that he was condemned to endlessly wander through the world and witness what he cannot share. When Scrooge comments on Marley's chains, the ghost replies by saying,

I wear the chain I forged in life.... I made it link by link, and yard by yard; I girded it on of my own free will, and of my own free will I wore it.

Marley's ghost is aware that Scrooge has also forged the same symbolic chain in life and risks eternal punishment if he does not transform himself and change his ways. Marley's ghost proceeds to tell Scrooge that he will be visited by three spirits before Christmas Day and joins the other restless spirits wandering throughout the night.