Do you think that regeneration or redemption is the main theme of Silas Marner?

One could certainly argue that redemption and regeneration are important themes in George Eliot’s Silas Marner.
This applies first to Silas’s journey in the text. A bitter, miserly old weaver, Silas is despondent when Duncey steals all of his precious gold coins. Silas has isolated himself from human relationships and contact after the failure of his first engagement. He was also framed for a crime he never committed. However, when Silas takes in a motherless child and names her Eppie, he finds renewed purpose in life. The closeness he eschewed for so long becomes a rejuvenating force in his life; Eppie becomes his surrogate daughter and companion, and without her, Silas would have easily died a penniless, grouchy old man by choice. This shows that love and human kindness can rejuvenate the soul.
Redemption is also a factor in Godfrey Cass’s story. Because of his embarrassment, Godfrey denies ever having been married to Eppie’s biological mother—even after the discovery of her corpse in the snow. This causes him to neglect Eppie as his child, even though he helps Silas care for her via financial support. However, Godfrey realizes that he was wrong to abandon his only child after Dunsey’s skeleton is found with Silas’s stolen gold. Godfrey’s guilty conscience forces him to confess to Nancy the truth about Molly and his daughter. Even though Eppie does not want to move in with her father and Nancy, Godfrey still redeems himself by remodeling Silas’s house once Eppie gets married. This shows that people who make bad decisions always have the ability to redeem themselves; it is never too late.