The Brahma Purana explains how An Ideal Brahmin should be and the Significance of Gayatri Mantra..
Describing about the qualities of an ideal brahmin, Sage Pulastya said— Once, Narada had asked Lord Brahma as to who was worthy of receiving Vishnu’s blessings.
Lord Brahma had told Narada that Lord Vishnu showered his blessings on those who engaged themselves in the service of brahmins. A brahmin should be virtuous and well versed in all the scriptures. A brahmin who does not observe the rituals as mentioned in the Vedas, brings disgrace to his ancestors. An ideal brahmin is respectful towards his parents, teachers and treats his guests with due honor. He never aspires for women other than his wife and chants the sacred Gayatri mantra everyday.
Goddess Gayatri is said to have manifested in the lineage of Sankhyayan. She is of fair complexion and fire is the symbolical expression of her mouth. Lord Brahma dwells on her forehead, Lord Vishnu in her heart and Lord Rudra has his abode in her braided hair. The Gayatri mantra consists of 24 letters and each of them is related with a specific deity. There is a mention of Gayatri mantra, which consists of 18 letters. It begins with the word ‘agni’ and ends with ‘swaha’. The mantra is as follows…
OM AGNERVAKPUNSI YAJURDEDIN JUSHTA SOMAM PIBA SWAHA.
A person, who chants the mantra for 100 times, becomes liberated from gravest of sin. The various deities related with the twenty-four letters of Gayatri Mantra are as follows…
1st letter — Agni
2nd letter — Vayu
3rd letter — Surya
4th letter — Akash
5th letter — Yamraj
6th letter — Varuna
7th letter — Brihaspati
8th letter — Parjanya
9th letter — Indra
10th letter — Gandharva
11th letter — Poosha
12th letter — Mitra
13th letter — Twashta
14th letter — Vasu
15th letter — Marudganas
16th letter — Soma
17th letter –Angira
18th letter –Vishwadeva
19th letter –Ashwins
20th letter –Prajapati
21st letter —All deities
22nd letter — Rudra
23rd letter — Brahma
24th letter — Vishnu
A devotee should then perform the ritual of ‘nyas’ by mentally establishing different words of the Gayatri mantra in the various parts of his body as given below…
OM BHUH —in the heart, OM BHUVAH — in the head, OM SWAH —in the top-knot, OM TATSAVITURVARENYAM–in the whole body, OM BHARGODEVASYA DHIMAHI —in both eyes, OM DHIYO YO NAH PRACHODAYAT —in both hands.
Regular chanting of Gayatri mantra bestowes similar virtues attained by the study of all the four vedas. A brahmin who does not know Gayatri mantra is considered to be worse than a shudra. Anybody who chants Gayatri mantra attains salvation.