In the 1953 movie, Ben Hur is gone a total of close to five years while in the novel it's considerably longer than that; he's a galley slave for over three years and then is in Rome for another five years, training in combat and becoming a champion charioteer. Arrius dies during this time (unlike in the film) and Ben Hur, his heir, is now a very wealthy Roman citizen. And he doesn't return directly to Jerusalem; he goes to Antioch on business and hears that his father's steward/slave Simonides still lives in the city (this occurs in part four).
When the Roman authorities were seizing all of the Hur lands and wealth, they tortured Simonides to get him to reveal the location of much of said wealth. He refused and was left broken in body, unable to walk. The shock of what happened killed his wife (not mentioned in the film) and he is now cared for by his sweet teenaged daughter Esther. This is one thing which I don't like about the film: it pretty much sidelines Simonides after Ben Hur's return. In the book, he's still sharp as a tack- and as hard as nails (except with Esther). Having saved most of the Hur family's monetary wealth, he made smart investments with it- mostly overseas where the Romans couldn't get their hands on it- and made the Hur fortune grow far greater than it already was. Absent of any Hurs to deliver this fortune to, Simonides and his daughter are living very well and prosperously in Antioch when Judah Ben Hur arrives at the door. He is admitted by Esther; this is the first time they meet, unlike in the film, and Judah does not have romance on his mind. He's there solely to see his father's steward. Simonides recognizes him right away (he looks like his father) but pretends not to, demanding that Judah produce evidence that he is who he says he is. Judah is dismayed by this: he's been gone for the better part of a decade, no doubt is presumed dead, and has no papers to prove his identity. He says as much, but asks Simonides if he has any knowledge of the fate of his mother and sister. Simonides tells him entirely truthfully that he was unable to learn of their fate. Ben Hur leaves sadly and Simonides, wanting to know more about young Hur who has appeared so suddenly, sends his servant Malluch (who doesn't have his tongue cut out) to keep an eye on him. Malluch befriends Judah without revealing his identity and they go to the arena where Judah catches sight of his erstwhile friend, now enemy, Messala who is training for an upcoming chariot race.
Meanwhile, Simonides has confided to Esther that he knows that Judah is indeed Ben Hur and she is confused as to why he pretended otherwise. Part of this is his natural caution; he wants to learn what kind of man Judah has become before committing to anything. But, he also points out, if he admits that Judah Ben Hur is alive, as a bond servant all of the wealth which they have- which he earned- technically belongs to Judah, as does he, and Esther for that matter. Esther, who was very much moved by Judah's obvious anguish over his mother and sister, tells Simonides that these things don't matter; they must do what's right.
None of this is in the film, of course, and the plots of novel and movie will diverge even further from here on out.