Once Brahmaa began to perform a sacrifice. As Saavitree, his wife, was busy with her household duties, she delayed in coming to the sacrificial ground. Consequently Brahmaa asked Indra to find a girl whom he could marry in order to perform the sacrifice. Accordingly Indra brought Gaayatree, a cowherd girl (gopatakatiyati) and Brahmaa married her.

Having come to know about the second marriage of her husband, Saavitree became highly enraged and cursed the gods, namely Indra, Rudra, Agni and others. Vishnu tried to propitiate Saavitree by uttering the aforesaid eulogy. She, being pleased, bestowed on Vishnu the boon that he would be unconquerable and also dear to His parents in all his incarnations.

It is well known that Saavitree and Gaayatree have been variously depicted in the Puraan and allied literature, They are regarded not only as identical but also as friends. In some places they are mentioned as the wives of Brahmaa and in a few places as his daughters. A somewhat similar relation of Saavitree to Saraswatee is also found in the Puraan. Since Saavitree is identical with Saraswatee, she is considered as having white omplexion.

Morning, noon and evening are called Sandhyaa. Saavitree is figuratively identified with these periods. The religious act performed at these three divisions is also called Sandhyaa, and Saavitree may be considered as identical with this act. The word may be directly applied to Saavitree if it is derived as to be worshipped in Sandhyaa.

The relationship of Saavitree, Gaayatree and Saraswatee may be explained in three ways :
(1) Saavitree is identical with the group (of three) consisting of
(2) Saavitree is identical with as well as with soft.

The first interpretation has its basis in such Vaidik statements. There are a number of interpretations of these three expressions (called Vyaahriti). They are usually taken as representing the three regions, namely the Earth, atmosphere and Heaven.

In the second interpretation "trayt" (a group having three parts) stands for Trayee Vidyaa ie the lore concerning the three kinds of Mantra namely Rig, Yaju and Saam. Usually Trayt refers to that part of the Ved which deals with the sacrificial acts (Karm Kaand) as distinct from the Upanishadik part which deals with Gyaan Kaand.
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From Shriram Sharma's "Gayatri and Savitri - 2 forms of one super power"
The primordial energy has two aspects - Gyaan and Vigyaan. Gyaan or wisdom includes consciousness, thinking, sentiments, beliefs and aspirations. It lies within man. Vijgyaan includes extrapolation of natural wealth and science of its application in day to day life. Wisdom lies within man’s consciousness and Vigyaan or science involves its application.

In Indian Mythology or Puraan it has been described as Brahmaa having two wives. One was Gayatri and the other was Savitri. Gayatri is the Goddess of Wisdom and Savitri is the presiding deity of science. Man’s body is matter hence its existence is looked upon as lying within the realms of Savitri. While marching ahead on the path of wisdom a man attains self control and progress. He attains the path of remaining happy and giving inspiration to others. He attains Self or God's Realization.

Two types of images of Primordial Energy can be found. One has one face, 2 arms, water pot in one hand, rosary and vehicle is a swan. This is Brahmi Shakti or Divine Energy. It is called Gayatri. Another image has 5 faces and is called Savitri.

The vehicle of Gayatri is a swan. Swan means royal swan, Param Hans that can separate water and milk, that eats pearls and vows never to eat worms etc. Rosary connotes meditation and books means self introspection via scriptural studies etc. This then is the image of maternal power. It is the presiding deity of human glory thus it has one face. The vehicle of Savitri is a lotus. Lotus means joy. There are lots of material pleasures. It has 5 faces. The body is made up of 5 elements and its psychic consciousness is made of 5 Praan or vital forces. The 10 arms of Savitri mean 10 senses of the body. It is through the power of the senses that the body functions. Amongst weapons those are painted in the photo that aid in material advancement and competition.

Gayatri predominates because when divine wisdom is imbibed such a personality is designed that if due interest is taken in the direction of economic arena one can generate lots of wealth for oneself and others too. But the arena of Savitri or science is limited to the material world. It is not necessary that a powerfully wealthy man is also rich in Divine Wisdom. Hence such a one is not that important. In the personality the soul predominates and body is minor. In the same way from the spiritual standpoint Gayatri predominates and Savitri becomes minor. And yet both need to be devoted to. Both have their importance in their own inimitable way. Thus all round spiritual aspirants make use of both and time and again apply their powers in their day to day lives.

In symbolic terms both are said to be wisdom, consciousness and material wealth. One (Gayatri) is Paraa Prakriti and the other is A-paraa Prakriti. Paraa Prakriti includes mind, intellect, psyche, ego and Divine Intellect or Ritambhar Pragyaa. This is the area of wisdom. The second wife is Savitri or A-para Prakriti or material energy or material nature. All movements and activities of matter are dependent on it. The movement in atoms, chemical reactions, electricity, heat, light, magnetism, ether etc are a part of it. Material Science by making use of these means, invent many things and thus augment material comforts. This very Apara Prakriti is called Savitri. This second energy is called Kundalinee.

There is no limit to conscious energy. Scholars, scientists, realized saints, super men, Rishi, thinkers etc progress in their respective areas by using this energy in their own way. On this basis for intellectual education school training, self introspection, association with realized saints, deep thinking and trance practices are carried out. All potentials regarding radiance of personality and divine aura are conjoined to this very area. The inner consciousness evolves with the aid of Para Prakriti practices and Gayatri Meditation.

The second energy is Savitri - material energy or activity. With the help of this Paraa Prakriti bodily activities of all creatures are carried out. In the human body many activities take place like inhalation and exhalation, blood circulation, sleep and awakening, digestion and excretion, heat and energy, electrical flow etc. Every object of the world is mobile. In this world the wheel moves ceaselessly in the form of creation, propagation and transformation. Animate and inanimate beings are marching ahead on the path of evolution. Every particle is forced to progress. The inspirational center of transforming inaction into activity is called A-paraa Prakriti that lies in Mahat Tattwa. It is this energy that directs movements of Sat, Raj, Tam, 5 elements, 5 Tanmaatraa etc. Siddhis (Divine Powers) and boons are got due to its benediction. This then is Savitri, the second wife of Brahmaa. Infinite special qualities of the human body like health, long life, strength, zest, valor, beauty etc are dependent on it.