Question
Are the upanishads later to the puranas?
Answer
There are some minor Upanishads as well which mention Puranas. All these Upanishads are counted among the 108 Upanishads as given in Muktika's list.
From the Paingala Upanishad's Adhyaya 4:
Whoever recites this Upanishad becomes as immaculate as Agni. He becomes as pure as Brahma. He becomes as pure as Vayu. He becomes like one who has bathed in all the holy waters. He becomes like one who has studied all the Vedas. He becomes like one that has undergone all vedic observances. He obtains the fruit of the recitation of Itihasas, Puranas and Rudramantras a lakh of times. He becomes like one that has pronounced Pranava (Om) ten thousand times, purifies his ancestors ten degrees removed and his descendants ten degrees removed. He becomes purified of all those that sit with him for dinner. He becomes a great personage. He becomes purified from the sins of the murder of a Brahman, the drinking of alcohol, theft of gold, and sexual cohabitation with Guru's wife, and from the sins of associating with those that commit such sins.
Now, from Tejobindu Upanishad's 5th Chapter:
The Vedas, Sciences, Puranas, effect and cause, Is vara and the world and the elements and mankind all these are unreal. There is no doubt of it. Bondage, salvation, happiness, relatives, meditation, chitta, the Devas, the demons, the secondary and the primary, the high and the low all these are unreal. There is no doubt of it. Whatever is uttered by the mouth, whatever is willed by sankalpa, whatever is thought by manas all these are unreal. Whatever is determined by the buddhi, whatever is cognized by chitta, whatever is discussed by the religious books, whatever is seen by the eye and heard by the ears, and whatever exists as Sat, as also the ear, the eye, and the limbs all these are unreal.
From the same Upanishad:
.. lightened and the non-enlightened, duality and non-duality, the conclusion of all Vedantas and Sastras, the theory of the existence of all souls and that of one soul only, whatever is thought by chitta, whatever is willed by sankalpa, whatever is determined by buddhi, whatever one hears and sees, whatever the guru instructs, whatever is sensed by all the organs, whatever is discussed in mimamsa. whatever is ascertained by nyaya (philosophy) and by the great ones who have reached the other side of the Vedas, the saying Siva destroys the world, Vishnu protects it, and Brahma creates it , whatever is found in the puranas, whatever is ascertained by the Vedas, and is the signification of all the Vedas all these resemble the horns of a hare. The conception I am the body is spoken of as the internal organ; the conception I am the body is spoken of as the great mundane existence ; the conception ( I am the body constitutes the whole universe.
And, from the Vajrasuchi Upanishad's last Chapter:
Such is the opinion of the vedas, the smrtis, the itihasa and the puranas. Otherwise one cannot obtain the status of a brahmana. One should meditate on his Atma as Sachchidanada, and the non-dual Brahman. Yea, one should meditate on his Atma as the Sachchidananda Brahman. Such is the Upanishad
I think this only goes to show that the era of the Upanishads is much later than that of the Vedas.
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