From Fundamentals to Rules: How religion evolves...
ॐ पूर्णमदः पूर्णमिदम् पूर्णात् पूर्णमुदच्यते |
पूर्णस्य पूर्णमादाय पूर्णमेवावशिष्यते ||
ॐ शान्तिः शान्तिः शान्तिः ||
And for those of you who cannot read devanagari...
om poornamadah poornamidam poornat poornamudkyate
poornasya poornamadaya poornamevaa vasisyate
om shanti shanti shantihi
(Remember 'Asatoma satgamaya...' ? Yup! That is from the Brihadaaranyaka Upanishad as well.)
In this, one of the earliest Upanishads, the Shanti Mantra talks about the nature of the Absolute. Brihadaaranyaka Upanishad is associated with the Yajur Veda (specifically the Shukla Samhita). Yajur Veda of course deals with the mantras associated with performance of rituals: the interpretation as well as the procedure.
As we jump to the Atharvana Vedaa, the shanti mantra suddenly becomes a shopping list! - Do this, Do that; don't forget this; God Help me! - The Realization of the Absolute is forgotten; the rules remain.
For instance, in the Mundaka Upanishad, The Shanti Mantra takes this form
ॐ भद्रं कर्णेभिः श्रुणुयाम देवाः ।
भद्रं पश्येमाक्षभिर्यजत्राः
स्थिरैरन्ङ्गैस्तुष्टुवागं सस्तनूभिः ।
व्यशेम देवहितम् यदायुः ।
स्वस्ति न इन्द्रो वृद्धश्रवाः ।
स्वस्ति नः पूषा विश्ववेदाः ।
स्वस्ति नस्तार्क्ष्यो अरिष्टनेमिः ।
स्वस्ति नो ब्रिहस्पतिर्दधातु
ॐ शान्तिः शान्तिः शान्तिः ॥
om bhadram karnebhihi shrunuyaama devaaha
bhadram pashyemaakshabhiryajatraaha
sthirairanngaistushtuvaagam sastanoobhihi
vyashema devahitam yadaayuha
svasti na indro vriddhashravaaha
svasti naha pooshaa vishvavedaaha
svasti nastaarksyo arishtanemihi
svasti no brihaspatirdadhaatu
om shanti shanti shantihi
For the record, The Yajur Veda (along with Rig and Sama) predate the Atharvana Veda.
Yet another example of how Religion starts of with good intentions but invariably ends up as a set of rules. The funda still makes sense but, over time, the rules tend to become irrelevant.
p.s. Couldnt find my hardbound copy of the Upanishads. Wikipedia to the rescue (for now). Gotta scurry to Landmark and pick up another set!