The four mantra-samhita books, characterized by their appellations Rik, Yajus, Sāma and Atharva are made up of mantrās. These are poetic verses, some of which are metrical and the remaining are not. There are three types of mantrās in the four collections namely rik or ŗk, yajus and sāma. An ancient authority characterizes the three types as follows: rik is a verse in one of the standard metres like gāyatri, anustup etc. The number of syllables in a verse defines its metre; a verse in gāyatri has 24 syllables divided into 3 pādās, lines. Sāman is a metrical verse chanted in an elaborate manner according to specific rules. The remaining verses are yajus. It is inappropriate to characterize the yajus mantrās as prose. The famous litany Shatarudrīya to the deity Rudra occurring in the chapters 16 and 18 of the shukla yajur veda or that in kānda 4, adhyāya 5, prapātţhaka 1, (4.5.1) of Taittirīya Samhita of the Krişhņa yajur veda is one such non-metrical poem.
Rigveda Samhita is a collection made up of only rik mantrās; Sāmaveda Samhita is made up of only Sāma mantrās. Both the Yajurveda Samhita and Atharvaveda Samhita contains both Rik mantrās and Yajur mantrās.
There is substantial overlap among the four Veda Samhitās. Ninety-five percent of the text of the entire Sāmaveda Samhita is in Rigveda Samhita. About 50 percent of the mantrās in Shukla Yajurveda Samhita and thirty percent of the mantrās in Atharvaveda Samhita are in Rigveda Samhita. Thus it is absurd to state that Atharvaveda Samhita is not sacred.
The total number of mantrās in the four Samhitās, Rig, Shukla–Yajur, Sāma and Atharva is roughly twenty thousand including repetitions.
We stated earlier that all the mantrās of the four collections are perceptions of deep spiritual truths and occult phenomena revealed to the rişhis. These verses couched their knowledge in heavy symbolism. Some moderns who do not care to understand the language of symbols label these verses as simplistic or childish.
The symbols used in these verses are of many types as will be clarified later. A majority of these symbols deal with yajna which is a Sanskrit word having several different connotations. This word is translated as rite or sacrifice. The outward ritual is only one aspect of yajna. In the vedic times, there was widespread performance of these rituals, which are fairly elaborate ranging in time over several days or even months. A typical ritual involves four types of priests, the fire-altar, the recitations from the mantra–samhita books and the physical offerings like the juice of the creeper Soma, the melted and clarified butter, ghŗta etc. Every outward ritual has a corresponding internal yajna occurring in the subtle body of the human performer of the yajna. The symbolism of the yajna will be clarified in the next two chapters. Since the Veda Samhitās frequently use the terms occurring in the yajna like the names of the four priests, the fire-altar etc., the entire Veda Samhitās are dubbed as ritualistic by persons who do not understand its symbolism. Some verses or whole hymns are recited at appropriate times in the ritual; but no one can point to the presence of the details of any ritual in a single hymn of the four Veda Samhitās. Many mantrās of the Veda Samhitās such as RV (1.1.1) explicitly declare that the priests in the yajna are not human beings, but the cosmic forces or deities like Agni, Indra; It is the deities like Mitra and Varuņa who Light the fire in the fire-altar, RV (1.36.4) etc.
Thus every verse of the Samhitās has a double meaning, the so called esoteric meaning or the deep meaning understood in these days by the rişhis and their disciples, and the external or exoteric or gross meaning understood by the commoners who attended the rituals. The commoners believed that by adoring the Gods such as Agni, Indra etc., by means of mantrās and rituals, their desires would be satisfied. The device of double meaning of the Mantra was necessary for preserving the secret knowledge from being misused by unqualified persons.
The mention of the double meaning of the Veda Mantra has a long history going back to the earliest known vedic commentator Yāska. In modern times it was Sri Aurobindo who championed the spiritual interpretation of the Veda.
RigVeda Samhita
It is a book of more than ten thousand mantrās, each in a specific metre, arranged in ten manalās. They were revealed to several sages or seers called as rişhis, more than one thousand in number. Some of them are women too like Vāk Ambŗņi, Lopamudrā, Sūryā, Apāla etc. Thus Hinduism is the only religion in which some of the earliest prophets were women also.
The spiritual meaning of some of the mantrās are transparent; the meaning of others becomes clear after understanding the underlying symbolism. We will discuss the details of symbolism in the next several chapters.
YajurVeda Samhita
It has two major recensions, Shukla and Krişhņa. They have both metrical and non-metrical poems. The Shukla Yajurveda has about sixteen hundred mantrās; about fifty percent of it is in Rigveda Samhita. It is made up of forty adhyāyās or chapters, the last one being the famous Işha Upanishad. It includes several famous hymns such as Shatarudrīya, Puruşha, Shivasankalpa etc.
We will mention here its verse (26.2), second verse in 26th chapter, which declares that all the mantrās of all the Vedās have to be taught to all persons, women or men, belonging to a high or low caste, or a stranger to the community.
Careless reading and translation have lead to the impression that Yajurveda Samhita is merely a book of physical rituals. As mentioned earlier, verses from this Samhita are recited systematically at various points in the physical ritual. At this point, we should make a clear distinction between the text of the Yajurveda Samhita and the commentaries on it by the brāhmaņa books and the sūtra books like āpastambha sūtra. Western translators like Keith or Griffith had no clue to the symbolism of the yajur veda samhita and hence they gave a ritualistic meaning for each verse based on the commentary in the brāhmaņa.
SāmaVeda Samhita
It is a book of about 2000 metrical verses, all of which are in Rigveda Samhita except for 75 of them. These verses are chanted in an elaborate way labelled udgīta. The text used for chanting is an expanded version of the basic text found in Sāma and Rigveda Samhitās, obtained by adding several syllables. The chanting notation in the written text Sāmaveda involves seven symbols, unlike the three in Rigveda Samhita. Sāmaveda Samhita is the foundation for Indian music with its basic seven notes. One of the brāhmaņa book associated with this Samhita is called Talavakāra, i.e., one who provides the beat or rhyme in the music.
AtharvaVeda Samhita
It has also names like brahma Veda suggesting its spiritual importance and bhishag Veda alluding to the many hymns in it dealing with healing in general. It has verses both metrical and non-metrical. It has about 6000 metrical verses of which about 1200 are in rig Veda Samhita also. It has a total of 731 sūktās, 80 of which have non-metrical verses or prose.
It has several interesting hymns dealing with different branches of knowledge. It gives the foundation of decimal notation for integers stating that the relation of one and ten, that of two and twenty etc., are all identical, AV (6.25.1, 2, 3; 7.4.1). It has the first definition of mathematical infinity stating that infinity is that which is left after subtracting infinity out of it, AV (10.8.29).
It has several interesting hymns dealing with society at large. It explicitly states that that society was ‘multi cultural’, i.e., it had people who belonged to different religions nānā dharmānām, and also people who spoke different languages. It calls upon people to make concord with strangers, AV (7.52.1).
It has the famous hymn to earth, bhūmi sūkta, AV(12.1), dealing with ecology. Its ideas on ecology go much beyond what the moderns have to say. It specifically notices the self-renewing nature of earth in its many aspects and calls upon human beings to act in ways which is in harmony with the general principles of earth.
It has several interesting hymns of spiritual importance such as the viewing the divine principle as a pillar skambha, AV(10.7) which supports the universe with its many planes dhāmāni, AV(10.7).
All Indian languages are full of epigrams or subhāşhitās (good-sayings) which reflect the many sided wisdom handed down by tradition. Many of these epigrams can be traced to the Atharvaveda. For instance the list of six psychological enemies ari shad varga such as lust kāma, anger krodha, greed lobha, delusion moha, arrogance mada and jealously mātsarya occurs in all languages. The Atharvaveda (8.4.22), also RV (7.104.22), explicitly refers to this list describing each quality by its associated animal or bird, the association itself being ancient. For instance the chakravāka birds denote lust, delusion by owl, jealousy by dog, destructive anger by wolf, greed by vulture and arrogance by eagle.