Gayatri and Yagya constitute the foundation of the Vedic Culture. While Gayatri imparts wisdom and pure intelligence, Yagya inspires corresponding creativity and actions. In talking of the Vedic age the images of the great rishis performing agnihotra-yagyas instantly flashes before our sight. In those days, apart from the rishis, the rich and the poor, the kings and citizens also had an equally deep faith and respect for Yagya and they used to sincerely participate in and lend wholehearted support for different kinds of Yagyas.
The rishis used to spend at least one-third of their lives in conducting Yagyas. It was a common belief and an observed fact in the Vedic Indian society that Yagya was essential for the refinement of human life from a shudra (i.e. a person living a life driven by animal instincts) to a Brahmin (i.e. a wise, knowledgeable, charitable person), and ultimately to a divine, great personality. Yagyas played an essential role in the all-round progress, prosperity and happiness in the Vedic age. This was indeed natural, as the philosophy and science of Yagya and the different modes of performing agni-yagya were discovered and developed by the rishis based on their deep understanding and in-depth research of the human psyche, the intricacies of the social fabric and the mysteries of Nature.
The brilliance and purity of agni (fire) appears to be a universal symbol for worship. The rituals of different religions affirm this fact. The first mantra of Rigaveda - the most ancient scripture of knowledge on Earth, quotes "agnimaye purohitam", signifying agni as a sacred symbol of God. This is what is referred to in different religious and spiritual scriptures as Brahmateja, Divine Flame, Sacred Glow, Divine Light, Latent Light, etc. The Vedic hymn "agne supatha raye" prays to this omnipotent, supreme power to enlighten and inspire us towards the righteous path. The same is meant in the phrase "dhiyo yonah prachodayat" of the great Gayatri Mantra.