Moore's poetry is suffused with a number of highly romantic symbols that feature throughout his whole body of work, expressing an increasingly idealised sense of Irish nationhood. This is particularly evident in poems like 'Dear Harp of My Country' in which the harp is personified as being a symbol of Irish nationhood that has been enslaved by 'the cold chain of silence', i.e. by the colonial oppression of the British. This was a level of symbolism that was to recur later in Joyce's short story 'Two Gallants' where Lenehan sees a harpist playing, harp similarly symbolised as a shamed and silenced woman, Éireann, the personified symbol of Ireland. Joyce's story self-consciously echoes the symbolism of Moore's poem.
The imagery of slavery is equally expressed in 'Come O'er the Sea' where the poet urges his lover to leave Ireland with him and to migrate to freedom where 'Love and Liberty's all our own' while at home in colonial Ireland the 'Land' is seen as for 'court and chains alone' i.e. the symbolism of the chains expresses an image of the Irishman being constrained by the laws of colonial Britain which he can only escape through exile and emigration.
Moore also consistently employs the symbolism of light and darkness throughout his poetry, dark being a symbol of darkness, obscurity, sadness and isolation, such as in 'At the Midnight Hour of Night' where the 'stars are weeping' for the lovers, juxtaposed to their earlier love which is associated with imagery of light and warmth where their 'life shone warm' in his imagination.