Vastu means material. And Sastra means science. Thus #Vaastu Sastra means material science. Generally term Vastu is used to refer to Earth and hence, #VastuSastra is science that deals with the human activities on the Earth.
(The following texts are extracts from Chapter 14, Vastu Sastra in author's BOOK: "A Tribute to the Ancient World of India")
So Vastu can be called as science of building construction and civil engineering but it is more than that. Vastu Sastra integrates material science and work of cosmic forces on human beings. Vastu Sastra brings in material well being for the dwellers in addition to turning cosmic forces as auspicious and human friendly.
Vaastu Sastra prescribes some kind of rules to be followed in the construction of a building. There are several rules prescribed in the planning and construction work starting form depth of foundation to the sizes of rooms and positioning of rooms according to their use, etc. For example, Central hall or room of a house is called Garbha and it is assigned to Brahma. Similarly northern direction is called Dhana Sthan and Lord Kubera is said to be dwelling in that direction. Western direction is awarded to Varuna (water god), Eastern direction to Indra (king of Devas), North east direction to Esana (Lord Siva), so it is suggested that Fresh drinking water should be drawn from North East direction because Siva dwells in that direction and because Shiva brought down Ganga waters from heavens. Southern direction is given to Lord Yama (god of death), South East direction to Agni (fire god), accordingly it is suggested that Kitchen should be placed in South East direction because Agni (fire god) dwells in this direction. South West direction is ascribed to Nirruta and North West direction to Vayu (wind god). Now let us examine if there is any correlation of Vastu Sastra to geography and history of the ancient Indus Valley culture and civilization. The following sloka is used in a ritual called ‘aMkuraarOpaNa’ . This ritual is conducted to invoke five Gods (paMca- pAlikas) while planting seeds for sprouting at the foundation ceremony before construction of a house.
मध्यॆ चतुर्मुखं विन्द्यात्पूर्वॆ तु इन्द्रमॆवच
दक्षिणॆच यमं विन्द्यात्पश्चिमॆ वरुणं तथा
उत्तरॆ धनदं विन्द्यात्पालिका स्थापनं क्रमात
madhyE caturmuKaM vindyAtpUrvE tu indramEvaca
dakShiNEca yamaM vindyAtpaScimE varuNaM tathA
uttarE dhanadaM vindyAtpAlikA sthApanaM kramAt
hymn we learn that Chaturmukha Brahma is at the Center of the Ritual Vedi (altar) and there is Vindhya at the Center. And this central place is surrounded by four directions and ruled by four gods respectively.
North East (Esana):
According to the following sloka, one who intends to construct a house has to prepare some sacred grains along with a copper plate with the following sloka inscribed on it. Then the plate should be planted in North East (Esana) corner of the house. This would fix and treat North East corner of a house against evil forces. This mantra is called as eeSaanya diSa digbhaMdana mahaa maMtra,
ड्ज़ल्र श्ज़ शपश्ल ॒ ॒॒
गृहस्त्यैशान्यां दिशि गर्तं खात्वा मूलिकादि संहितं यंत्रं निक्षिप्य पंचॊपचारैस्संपूज्य अभिमंत्रयॆत.
gRuhastyaiSaanyaaM diSi gartaM khaatvaa mUlikaadi saMhitaM yaMtraM nikShipya paMchOpachaaraissaMpUjya abhimaMtrayEt.
ऒं नमॊ भववतॆ अघॊर वीरबडबानल सर्वतॊमुख शरभ साळ्वॆस्वराय अष्टकॊटि त्रिशूल हस्ताय स्पटिक वर्णाय वृषभ वाहनारूढाय ईशानाय ऒं खॆं खॆं खं खं खां फं रं रं घॆं घॆं घं घ्र्सौ ऒं शं आमुकगॊत्रॊत्पन्नस्यामुकनाम्नः गृहस्तैशान्य दिशं भंधय भंधय
OM namO bhavavatE aghOra veerabaDabaanala sarvatOmukha Sarabha saaLvEswaraaya aShTakOTi triSUla hastaaya spaTika varNaaya vRuShabha vaahanaarUDhaaya ISaanaaya OM khEM khEM khaM khaM khaaM phaM raM raM ghEM ghEM ghaM ghrsou OM SaM aamukagOtrOtpannasyaamukanaamnaH gRuhastaiSaanya diSaM bhaMdhaya bhaMdhaya
According to above mantras, God of North East direction is called as Eesana and He holds a Trident in his hands (Trisula Hastaya ), He is white crystal colored (Spatika Varnaya ) and He has a Bull as his mount (Vrushabha vahanarudhaaya ). These descriptions of the God of Esana invariably hold good for Lord Siva. So that Eesana direction is allotted to Lord Siva. And let us also look at the following sloka from Rig Veda,
कृतॊद्वाहं तु दॆवॆशं गच्छंतं समरुद्गणम
दर्षयामास दुर्मॆधा हुंकृतश्च महात्मना
kRutOdvaahaM tu dEvESaM gacCaMtaM samarudgaNam
darShayaamaasa durmEdhaa huMkRutaSca mahaatmanaa
Meaning: “After decimating Cupid God Manmadha, Lord Siva sped away towards North East along with his Maruta ganas.”
By looking at the map at Picture 14.3 we can see that Harappa then Siwalik hills and thence Kashmir is in the North East direction of Ganweriwala. Kashmir is a noted abode of Siva since ages. And the famed Gandhamadana mountain (abode of Siva) is located here in Kashmir only. From the above observations we can easily understand that Ganweriwala is the point from where Siva begun his journey to North East where mount Gandhamadana is situated. And hence Ganweriwala was the Center of Universe of ancient Indians.
By the way, let us also observe that Devi Parvati is alluded to be daughter of King of Hills (Shaila Raja Putri). Before Siva sped to Gandamadana usually Devis are worshipped as Goddesses of Water bodies (Saraswati) and Prasavitri, Goddess of Prasava (Savitri/Savita). But after Siva made Gandamadana Parvata as his abode he started worshipping Devi placed in that Hill. That is why She is called as Parvati (Goddess of Hills).
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