As the caves were excavated for the residence of Jain monks, it is reasonable to expect that their architecture and art would yield substantial information about contemporary religious beliefs and practices. That, however, is not the case: while the architecture of the caves only attests to the rigours of Jain ascetic life, there is no early relief which can definitely be regarded as indisputably illustrating Jain religious mythology.
But, even from the scanty evidence, it is clear that Jainism, as practised in those days in this part of the country, did not involve the worship of images, for not a single Jain Tirthankara appears in the original carvings on the caves. In the absence of any early image it is difficult to identify the Jina of Kalinga, mentioned in the inscription of Kharavela, with the image of a Tirthankara.
On the other hand, it appears that the worship of symbols was in vogue at that time among the Jain's of this centre as among the Buddhists. Cave-5 ('Jaya-Vijayagumpha') of Udayagiri and Cave 3 (Ananta-gumpha) of Khandagiri, for example, depict a tree being worshipped by devotees with floral offerings. Again, Cave-9 (Manchapuri) of Udayagiri shows an unidentifiable symbol being worshipped, probably by a royal family.
On the back wall of Cave-3 (Ananta-gumpha) of the other hill appears a nandipada on a pedestal flanked on either side by a set of three symbols, a triangle-headed one (bhadrasana? or sthapana?), srivatsa and svastika, without forming part of any scene, all of which are also represented on the Jain ayagapatas from Mathura. These symbols are regarded by the Jain's as of good omen and form four of the eight auspicious objects (ashtamangalas) often worshipped by the Jainas.
What cult-object was enshrined in this religious edifice is difficult to say, but taking reference of the apsidal structure of the apsidal structure on Udayagiri, one things definite that it was a symbol and not an anthropomorphic icon of a Tirthankara.
When, however, in medieval times some cells of Khandagiri were reconditioned to serve as sanctuaries, as in other parts of the country, a developed Jain iconism consisting of images of Tirthankaras and their sasana-devis.