In Charles Dickens' A Christmas Carol, how is Marley's chain a symbol?

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.