The change in the villagers' perception of Silas was very gradual and directly proportional to the changes in Silas, himself.
At first they thought that Silas was scary, enigmatic, even mean and unapproachable. This was because Silas himself had made himself unapproachable, isolated, and prone to enigma with his attitude towards people and his lack of interest in being part of the community.
When the day came that his gold was stolen, Silas began to lose his mind, ventured out of the house and ended up at the Rainbow Inn in a form of panic attack- which caused panic in a way in those present.
When he began to accuse people, he was angry so he made them angry as well.
But when he finally cowed down and broke down, his pain was so sincere, and his frustration so evident that he touched the hearts of the people. They immediately quit their ideas about him and saw a very real person, immensely wounded and who has hit rock bottom.
Then, compassion hit because they saw themselves in his position, identified with him greatly, and offered their condolences and help to at least bring him back to sanity.
In general, the people of Raveloe brought together the most significant characteristics of a close-knit community: Charity, cooperation, and unity because nevertheless they were clearly aware that Silas Marner was still one of them, regardless of being an isolated person. Silas was part of Raveloe.