Mundaka Upanishad: ~ “The rituals and the sacrifices described in the Vedas deal with lower knowledge.+

Sage Sankara pointed out that those rituals could in no way bring about wisdom, much less Moksha.

Sage Sankara gave religious, ritual, and dogmatic instruction to the populace, but Advaitic wisdom only to the few who could rise to it.

If you mix Advaitic orthodoxy with Advaitic wisdom creates confusion, because they mix up the two viewpoints.

Thus, they may assert that ritual is a means of realizing Brahman, which is absurd.

Indulging in Non -Vedic rituals(Puranic Rituals) in place of Vedic rituals are enveloped in still greater darkness, in other words, they are extremely foolish, fall into an awful hell of pain and sorrow, and suffer terribly for a long time."

Thus Puranic karmas are not Vedic karmas as per Yajur Veda.

The Puranic karmas are introduced to suit the mass mindset of that time, by the founders of present-day Hinduism by keeping the Vedas as their base. They also introduced a new modified belief system on Puranic Gods with a new code of conduct to revive the Vedic religion, which was in ruins in the hands of Buddhism and Jainism.

Thus, present-day Hinduism with diverse beliefs is not a pure Vedic religion.

Thus, this hotchpotch ideology is the greatest obstacle to the realization of the ultimate truth. That is why Buddha rejected the Vedas.

 Sage Sankara: ~ 11. As regards the rituals, the person who performs rituals and aspires for rewards will view himself in terms of the caste into which he is born, his age, the stage of his life, his standing in society, etc. In addition, he is required to perform rituals all through his life. However, the Self has none of those attributes or tags. Hence, the person who superimposes all those attributes on the changeless, eternal Self and identifies the Self with the body is confusing one for the other; and is, therefore, an ignorant person. The scriptures dealing with rituals, rewards, etc. are therefore addressed to an ignorant person. (Adhyasa Bhashya)

Sage Sankara:~ 11.1 ~The scriptures dealing with rituals, rewards, etc. are, therefore, he says, addressed to an ignorant person. (Adhyasa Bhashya)

Sage Sankara   :~ 11.2. In short, a person who engages in rituals with the notion “I am an agent, doer, thinker”, according to Sage Sankara, is ignorant, as his behavior implies a distinct, separate doer/agent/knower; and an object that is to be done/achieved/known. That duality is Avidya, an error that can be removed by Vidya. (Adhyasa Bhashya)

Sage Sankara viewed this as a distortion of the Upanishad ideals. To play down the prominence given to rituals by the Mimamsakas, Sage Sankara relied on the idea of Avidya He bracketed the ritualistic approach with Avidya and called it an “error.” 

Thus Advaitic orthodoxy has to be discarded to realize the ‘Self’ hidden by the ‘I’, which is ignorance.

Sage Sankara states wisdom (Vidya) can eliminate ignorance (Avidya); but the ignorance it eliminates is not real, because it has no existence of its own. Once the error is removed the Brahman (God in truth) will reveal of its own accord. 

Remember:~

Mundaka Upanishad: ~ “The rituals and the sacrifices described in the Vedas deal with lower knowledge. The Sages ignored these rituals and went in search of higher knowledge. ... Such rituals are unsafe rafts for crossing The sea of samsara, of birth and death. Doomed to shipwreck are those who try to cross The sea of samsara on these poor rafts. Ignorant of their own ignorance, yet wise in their own esteem, these deluded men proud of their vain learning go round and round Like the blind led by the blind.

The essence of Mundaka Upanishad: ~ “Do not be satisfied with rituals, yoga, etc., which are good in their own way, but inquire. Into what? Brahman and Atman are things you can never see. So do not inquire into them. Inquire into the world around you, which you can see.

Science tells you it is passing away every second. Everything is dying repeatedly. Where is it going? Thus, you follow up your inquiry into what you can lay hands on. How can you inquire into Atma which you cannot see? So first we deal with the known and seen, this inquiry leads up to the unknown in the end.

The wisdom consists in knowing the truth, that everything (mind or physical existence) is consciousness.

Freedom (ultimate truth) is always there yet one does not know it. But to those whose reason is turned away from physicality and who have attained the serenity of the Soul, the Self is quite near to realizing the ultimate truth or Brahman.

In the past, Self-knowledge or Brahma Gnana or Atma Gnana was imparted only to a few because the Sages of truth had preserved it people were more interested in their religious beliefs. Nowadays people are more advanced and capable of understanding assimilating, and realizing the truth beyond form, time, and space.

As the seeker starts his journey he may find it difficult in the first as his understanding matures his subconscious will start dropping the dualistic egocentric knowledge and start accepting the Soul-centric Self-knowledge or Brahma Gnana or Atma Gnana. : ~ Santthosh Kumaar