To the Vedic priests, yajna was the means to invoke gods and seek their blessings and favors. They performed them for various purposes and at various times during the year, at the time of sowing, at the time of harvest, at the time of initiating some important social event or before going to wars. One very popular yajna of those days was the Asvamedha Yajna, or the Horse Sacrifice which used to be performed by powerful kings to mark their victory and suzerainty. Outwardly, the horse symbolizes the divine power of the king and inwardly it symbolizes Brahman himself. Just as Brahman endlessly expands in all directions, the power of the king is expected to grow in the same manner with the sacrifice.
Thus, each Yajna has an outer aspect and an inner aspect. The outer aspect of yajna consists of all that one can see. It includes the preparation, the participants, the altar, the kindling of consecrated fire, the wood used to keep the fire going, the flames, and the sacrificial material used as offerings and oblations, the prayers and chants, the remains of the offerings, the gifts and so on. All this is the material aspect of the Yajna.
The inner or hidden aspect of Yajna is known to those who are familiar with the Vedic rituals. The yajna is the means of worshipping the highest God or ones own inner self. It symbolizes creation itself and every aspect in it, in which there is an exchange or transference of Nature’s materiality and its numerous manifestations. The sacrifice involves the act of giving and taking, and thereby symbolizes the transformative aspect of Nature and the interdependence of worlds and beings. It points to the need to live in harmony with the rest of creation and the importance of transcending selfishness and self-interest.
Even when you strive to achieve your personal goals, you should not ignore your obligatory duties and your commitment to the order and regularity of the world. The Vedas clearly identify human selfishness as a major disrupting factor in the orderly progression of life. If people live for themselves and ignore their collective responsibilities towards each other, gods and other living beings, the world will be in chaos. Hence, they equate selfishness with evil itself.
We learn the same from modern science also, which affirms that you cannot solely live by yourself. It is common sense wisdom that if you want to live in peace, you must live responsibly and ensure the preservation of life around you, just as you cannot pollute the waters of a pond from where you draw your drinking water. Thus, sacrifices are meant to help you outgrow your selfishness and participate in sacrificial duties to ensure the continuation of the worlds and discharge your obligation to God who is the upholder of all.
In the Bhagavad-Gita Lord Krishna explains that every aspect of a ritual of sacrifice, represents Brahman namely the act of offering, the oblation, the sacrificer himself and the sacrificial fire as well (4.23). In the subsequent verses he lists various types of sacrifices which people perform for various reasons and aims (4.25-4.30) and concludes that the sacrifice in the form of knowledge is superior to the sacrifice which is done with material things. In the ninth chapter he declares, ” I am kratu (Vedic ritual), I am yajna (sacrifice), svadha (offering), ausadham (medicine), mantra (chant), ajyam (ghee), agni (fire), and hutam (burnt offering). In Chandogya Upanishad, the yajna is compared variously to the world (section 4), the rain god (section 5), the earth (section 6), man (section 7) and woman (section 8). The comparison can be summarized in the table as shown below.
| Parts of Yajna | World as Yajna | Rain as Yajna | Earth as Yajna | Man as Yajna | Woman as Yajna |
| Fire | world | rain | earth | man | woman |
| Fuel | sun | air | year | speech | sex organ |
| Smoke | rays | cloud | space | breath | desire |
| Flame | the day | lightening | night | tongue | vulva |
| Coals | the moon | thunder | quarters | eyes | friction |
| Sparks | stars | thundering | intermediate quarters | ears | pleasure |
| Oblation | faith | soma | rain | food | semen |
| The result | soma | rain | food | semen | fetus |
The physical or the outer aspect of the Vedic rituals has always been viewed with suspicion by the followers of renunciant paths and seekers of knowledge and truth. Several Upanishads declare the knowledge of the sacrificial rituals as ignorance or lower knowledge, which leads to rebirth and continuation of mortal existence. In Satapatha Brahmana we are told that gods and demons tried to perform a sacrifice. Demons, who think that the body is the soul, tried to perform it externally, while gods kindled fire within themselves and thereby became immortal. The Mandukya Upanishad is very clear in its opinion about the Vedic sacrifices. It declares, “Unsteady are the boats of 18 forms of sacrifice, which are part of inferior karma. The deluded, who take delight in them thinking that they would lead them to good, will fall again into old age and death.” It reaffirms the same opinion in the following words,” These deluded men who regard sacrifices and works of merit as most important do not know any other good. Having enjoyed in the high place of heaven, which is won by good deeds, they enter again this world or still the lower ones.” Thus, sacrifices have the same consequences as desire-ridden actions because although they are called sacrifices for namesake, they are performed out of desires only. The same Upanishad also declares the knowledge of the Vedas and rituals, grammar, etc., to be the lower (apara) knowledge, while the higher (para) knowledge is that one by which the Imperishable Brahman is realized. Almost a similar view is echoed in the Bhagavad-Gita by Lord Krishna who cautions us against empty ritualism (11.48). The knowers of Vedas who worship God through sacrifices would ascend to heaven and return from there.(9.20&21), but they would not attain liberation.