Tradition is important to the villagers of Silas Marner's Raveloe. As an agricultural community, Eliot suggests, the village has changed little in hundreds of years. Anything new—like Silas's loom, or Silas himself—is suspicious. And so tradition is both good and bad. It holds communities together, but it can also shade into something like habit, and habit can keep people apart. In the context of Eliot's religious interests, it's also worth pointing out that the Anglican church has traditionally (so to speak) been imagined as a stool resting on three legs: Reason, Scripture (the Bible), and Tradition. In the Anglican church, tradition, or what people have always done, is just as important as what the Bible says.
In Silas Marner, tradition is connected to agriculture and novelty is connected to industrialization. An industrialized society can have no traditions.
Eliot suggests that tradition can isolate individuals as much as it can bind together communities.