Animals symbolize the innocent and the oppressed in the poem. They also symbolize various emotions, qualities, and facets of human behavior, emphasizing how all living creatures are interconnected.

Blake often takes traditional symbolism associated with animals and expands on it. For instance, the skylark in Line 15 is traditionally a symbol of joy, its singing heralding summer. Since the skylark is a symbol of joy, its wounds represent a double cruelty. Thus, its pain stops an angel from singing. Similarly, in Line 9, the dog—a symbol of loyalty—is starved by its Master. The implication is that the dog is rewarded for its faith in its master with sadistic cruelty. In Line 11, a horse, a traditional symbol of hard work, is rewarded for this perseverance by being misused or overworked on the road. Often, the animals are anthropomorphized, linking their suffering with the suffering of oppressed humans. For instance, in Line 17, “the Game Cock clipd & armd for fight” is implicitly compared to a human gladiator forced to fight for the entertainment of others.

Animals also represent the wisdom and knowledge of innocence, as well as the Christian figures of Jesus Christ and the Holy Spirit.