The foundation of Hindu "Sanatan Dharma" are Vedas and all the principles of Sanatan Dharma are taken from the Vedas therefore Vedas are called Shabda Brahma (Lord in the word) in Sanatan Dharma.
And all Shastra are considered as limbs of Vedas from which Jyotish Shastra (Astrology) is considered as the Netra (eyes) of the Vedas that is why Indian astroloogy is also called Vedic Astrology.
As we need to do some efforts to get butter from the milk in the same way
we can get Jyotish Gyan from the Vedas but without Adhyatma Gyan it cannot be obtained from the Vedas,
that is why astrology is considered as Adhyatma Vidya(spiritual science).
Vedic astrology has three phases Hora, Tantra and Samhita:-
- Hora is for muhurt, lagan etc .
- Tantra includes Horoscope .
- Samhita is for panchang and other principles.
Through Vedic astrology we can know about any person's past, present and future that's why Vedic astrology is also named as "TrikaalVidya" and not only person we can predict about political aspects, economic, market and other aspects of an Institution, Company, Bussiness etc.
Vedic astrology is not only the oldest but it is the first astrology science of world.