The Dog in Mediæval Art symbolises Fidelity and appears on monuments at the feet of women, signifying affection and faithfulness; and at the feet of men, signifying courage and magnanimity. When the dog appears on the tombs of Crusaders, it is to indicate that they followed the standard of the Lord as a dog follows its master.
Other animals in Christian Art symbolise respectively:
The Lamb, which is reminiscent of the Paschal Lamb of the Exodus, appears on Church plate and decorations, and is usually depicted carrying a banner bearing the Cross, sometimes with blood issuing from its breast caught in a chalice.
The Pelican is the symbol of Charity and the emblem of the Atonement. It is generally represented on the nest feeding its young from the flesh of its breast.
The Phœnix, owing to its traditional rejuvenation every hundred years, is the symbol of the Resurrection.
The Dove is an emblem of Peace, Fidelity and of the Holy Spirit.
The Fish was adopted by the early Christians as the symbol of Purity and Faith. It conveys a comparison of the Christian passage through life with the fish passing through salt water still remaining fresh, and is occasionally suggested in the Vesica Piscis, which it resembles in general shape.
Association of Human and Animal Qualities
Such arbitrary creatures as the Sphinx, the Winged and Man-headed Bull and Lion, and the Griffin, were invested with symbolic meaning in the association of qualities—animal and human; and probably had their origin in an early belief in Totemism.