The religion of Champa was practically identical with that of Camboja. If the inscriptions of the former tell us more about mukhalingas and koshas and those of the latter have more allusions to the worship of the compound deity Hari-hara, this is probably a matter of chance. But even supposing that different cults were specially prominent at different places, it seems clear that all the gods and ceremonies known in Camboja were also known in Champa and _vice versa_. In both countries the national religion was Hinduism, mainly of the Śivaite type, accompanied by Mahayanist Buddhism which occasionally came to the front under royal patronage. In both any indigenous beliefs which may have existed did not form a separate system. It is probable however that the goddess known at Po-nagar as Bhagavatî was an ancient local deity worshipped before the Hindu immigration and an inscription found at Mi-son recommends those whose eyes are diseased to propitiate Kuvera and thus secure protection against Ekâkshapingalâ, "the tawny one-eyed (spirit)." Though this goddess or demon was probably a creation of local fancy, similar identifications of Kâlî with the spirits presiding over cholera, smallpox, etc., take place in India.
The social system was theoretically based on the four castes, but Chinese accounts indicate that in questions of marriage and inheritance older ideas connected with matriarchy and a division into clans still had weight. But the language of the inscriptions is most orthodox. King Vikrântavarman[349] quotes with approval the saying that the horse sacrifice is the best of good deeds and the murder of a Brahman the worst of sins. Brahmans, chaplains (purohita), pandits and ascetics are frequently mentioned as worthy of honour and gifts. The high priest or royal chaplain is styled Śrîparamapurohita but it does not appear that there was a sacerdotal family enjoying the unique position held by the Śivakaivalyas in Camboja. The frequent changes of capital and dynasty in Champa were unfavourable to continuity in either Church or State.
Śivaism, without any hostility to Vishṇuism or Buddhism, was the dominant creed. The earliest known inscription, that of Vo-can, contains indications of Buddhism, but three others believed to date from about 400 A.D. invoke Śiva under some such title as Bhadreśvara, indicating that a temple had been dedicated to him by King Bhadravarman. Thus the practice of combining the names of a king and his patron deity in one appellation existed in Champa at this early date[350]. It is also recorded from southern India, Camboja and Java. Besides Śiva one of the inscriptions venerates, though in a rather perfunctory manner, Umâ, Brahmâ, Vishṇu and the five elements. Several inscriptions[351] give details of Śivaite theology which agree with what we know of it in Camboja. The world animate and inanimate is an emanation from Śiva, but he delivers from the world those who think of him. Meditation, the practice of Yoga, and devotion to Śiva are several times mentioned with approval[352]. He abides in eight forms corresponding to his eight names Śarva, Bhava, Paśupati, Iśâna, Bhîma, Rudra, Mahâdeva, and Ugra. He is also, as in Java, Guru or the teacher and he has the usual mythological epithets. He dances in lonely places, he rides on the bull Nandi, is the slayer of Kâma, etc. Though represented by figures embodying such legends he was most commonly adored under the form of the linga which in Champa more than elsewhere came to be regarded as not merely symbolic but as a personal god. To mark this individuality it was commonly enclosed in a metal case (kosha) bearing one or more human faces[353]. It was then called mukhalinga and the faces were probably intended as portraits of royal donors, identified with the god in form as well as in name. An inscription of 1163 A.D. records the dedication of such a kosha, adorned with five royal faces, to Śrîśânabhadreśvara. The god, it is said, will now be able to give his blessing to all regions through his five mouths which he could not do before, and being enclosed in the kosha, like an embryo in the matrix, he becomes Hiraṇyagarbha. The linga, with or without these ornaments, was set on a _snânadroṇi_ or stone table arranged for receiving libations, and sometimes (as in Java and Camboja) four or more lingas were set upon a single slab. From A.D. 400 onwards, the cult of Śiva seems to have maintained its paramount position during the whole history of Champa, for the last recorded Sanskrit inscription is dedicated to him. From first to last it was the state religion. Śiva is said to have sent Uroja to be the first king and is even styled the root of the state of Champa.