Is the objective of vedas spiritual prosperity or material prosperity?
The ultimate purpose of the Vedas can be understood by reading the Bhagavad Gita.
In 15.15 Lord Krishna says:
sarvasya caham hrdi sannivisto
mattah smrtir jnanam apohanam ca
vedais ca sarvair aham eva vedyo
vedanta-krd veda-vid eva caham
I am seated in everyone's heart, and from Me come remembrance, knowledge and forgetfulness. By all the Vedas am I to be known; indeed I am the compiler of Vedanta, and I am the knower of the Vedas.
By reading this verse, one can very easily understand that the actual purpose of the Vedas is to understand Krishna. The Vedas primarily deal with Dharma (religiosity), Artha (Wealth), Kama (Pleasure) and Moksha (Liberation).
However, from the Bhagavad Gita we can understand that if one is following the Vedic way of life to the tee, but has still not understood that the ultimate goal is Krishna, all his endeavours are in vain.
Actually, this is the real secret teaching of the Vedas - understanding Krishna. It is very secret and hence not many people understand or realize it.
In fact Krishna himself says in the Gita (7.3):
kascid yatati siddhaye
yatatam api siddhanam
kascin mam vetti tattvatah
Out of many thousands among men, one may endeavor for perfection, and of those who have achieved perfection, hardly one knows Me in truth.
And how can one know Krishna?
Krishna can only be known through devotional service, i.e., Bhakti. Knowledge, Karma, Charity, Austerity in themselves are not enough to understand, unless they are anointed with Bhakti. So, if one somehow gets to know about this secret of the Vedas then one should take to the process of devotional service to Krishna with great faith.
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