1. Triads or Triples of Om त्रिमूर्त्ति । “But when considered as a triliteral word consisting of a, u, m, (अ, उ, म), Om implies, the three Vedas, the three states of human nature; the three divisions of the Universe; the three deities, agents of the three states of things—the creation, preservation and destruction; or properly speaking; the three principle attributes of the Supreme Being. In this sense it implies in fact the Universe controlled by the Supreme Being.” Rám Mohun Roy.
2. Their External Manifestations. ब्याहृतिः । The idea of the trisection of the circle of Om followed that of its bisection, together with that of the three fold division of Divine nature, much earlier in the minds of the Aryans of India, than the three sectors of the circle were unfolded by Euclid, and the mystery of the tri-une nature of the Divinity was discovered by the divine Plato, or that of the three persons in the God-head was revealed by the Gospel. But not content with this discovery, the ancient sages applied this triplicate division of Om to many other things as the three fold manifestations of the One Deity represented by the triliteral and trilateral figure of Om, and fell to their adoration, until they were recalled to the worship of the invisible unity of Om by the Vedánta doctrines. We shall now see these triples called the Vyáhritís (व्याहृति) or three fold manifestations in their order.
1. The 3 Vedas. त्रयो बिद्या बेदत्रयः । Om represents the three Vedas by its three letters, viz; the Rik, Yajur and Sáman, consisting of the Hymns, Ceremonies and Psalms. The first like the hymns of Hesiod and Orpheus, the second like the Levitican laws, and the third resembling the Psalms of David, all of which are said to be of Divine origin.
2. The 3 States. ॐ गुणत्रयं । These have no apposite terms in English, and are variously rendered to express the states of quietism, action and passion or excess of a feeling, leading to error.
3. The 3 Worlds. ॐ भूर्भुबः स्वर् । The earth, sky and heavens, called the three great evolutions (महा ब्याहृति) of Om. But those were afterwards subdivided into twenty one (3×7) each named as Om (ॐ त्रिसप्तं) as in the beginning of Atharva Sanhitá ॐ त्रिसप्ता ये परियन्ति बिश्वाः—“The Universe composed of thrice seven worlds.”
4. The 3 states of things. श्रवस्थात्रयं । These are the creation, preservation, and destruction of all things (सृष्टि, स्थिति, प्रलय), or as philosophically called their evolution, sustentation and dissolution (उत्पत्ति, स्थिति, ध्वंस), and their agents, Brahmá the creator, Vishnu, the preserver, and Siva the destroyer of each and all, corresponding with Jupiter, Neptune 5. The 3 Agencies Personified त्रि मूर्त्ति ।and Pluto, and Osiris, Horus and Typhon (ब्रहमाबिष्ण्वीशाः). But this trinity is refuted by the Vedántic doctrine of unity, which repudiates a secondary cause. (सृष्टि स्थिति लयादीनां नान्य कर्त्ता द्वितीयकं). The Maitrí Upanishad makes mention of many more triads which were glorified with the aforesaid hallowed epithet Om (VI. 5.) Viz. the following:—
1. The Trisex Divinity. Om composed of the three genders, masculine, feminine and neuter (स्त्रीपुन्नपुं). But the Vedánta refutes the generic distinctions of the One unknown (नपण्डनपुमान् शक्तिः).
2. The 3 Elemental forms. The fire, wind and sun, (सूर्य्याग्नि बायु), the three powerful manifestations of the Deity each of which had its votaries in the early fire, wind and sun worshippers of India.
3. The 3 Agencies as above. The creation, preservation and destruction of things in the forms of Brahmá, Vishnu and Siva as said above.
4. The 3 Fires. अग्नित्रयः । Om the three sacrificial fires called the दक्षिणा, गार्हपत्य and आह्वनीयाग्न्यः, which were continually preserved in families.