Mockingbirds are known for their beautiful and peaceful songs, and they are often associated with innocence, purity, and harmlessness. In the novel, Boo Radley is a secretive and mysterious character, who is often perceived as a threat or an outcast. However, just like the mockingbird, Boo Radley has a gentle and kind nature, and he poses no harm to anyone. He observes the world from the shadows and quietly provides assistance to the protagonist, Scout Finch, and her brother Jem.
Furthermore, the mockingbird symbol is associated with the theme of injustice in the novel. Mockingbirds are often harmed or killed for no reason, just as innocent individuals can be hurt by the prejudices and actions of others. Boo Radley is a victim of prejudice and misconceptions, and he is often judged negatively by the community. Despite his gentle and kind nature, he is labeled as an outsider and is feared and avoided by most people in Maycomb.
In contrast, Scout and Jem are able to see past these prejudices and recognize Boo's true character. They develop a friendship with him, even though he remains largely hidden and enigmatic. This friendship becomes a symbol of hope amidst the darkness of intolerance and injustice that permeates the novel.
Just as the mockingbird's song is a source of joy and beauty in the natural world, Boo Radley's presence and actions, though often hidden and misunderstood, bring a sense of hope and goodness into the lives of Scout and Jem. Despite the harsh realities and prejudices of society, the novel suggests that there are still individuals like Boo Radley who, though different or misunderstood, are capable of great kindness and empathy.