Rg-veda
Devaninda itself is directly traceable to the Śruti.
RV_6,061.03a sarasvati devanido ni barhaya
4000 + years ago, our ancestor, Bharadvāja, invoked the riverine form of Sarasvatī to destroy the revilers of the Devas.
About 2500 years later, Satti Nāyanār, 1 of the 63 great Śaiva saints, would mete out justice to abusers of Śiva & Śivabhaktas by cutting off the tip of the tongue presided over by that Sarasvati.
Brihaspati is also hailed in such a role - RV II 23 8 has exactly the same words, ‘devanido ni barhaya’ ; RV I 152 2 (to Mitra & Varuna) also features dread sanction meted out upon the ‘devanido’ … and I’m sure other examples for the concept abound within the Shruti.
One might observe, for instance, RV X 125 6 - wherein Rudra is called upon (empowered by Vak) to smite the ‘brahmadviṣ’ : those hostile / antagonistic to the religion & its operative ritual elements [‘brahman’ in the older sense], for a start.
atharva-veda
Source: TW
It would not be correct to say that the concept of Devaninda does not exist in the Vedas and did not exist before 8th century AD. It certainly did.
In the Vedas, there is a frequent reference to देवपीयक/देवपीयू. This compound is a synonym of देवनिन्दक and comprises देवः+ पीयक(reviler)= reviler of the Gods. It means exactly the same as Devaninda.
This word is frequently mentioned in Vedic literature from Atharvaveda onwards. Attached are references from Monier Williams Sanskrit dictionary and Alexander Lubotsky’s Indo Aryan lexicon for the meaning of the word. The Vedas are regarded by practicing Hindus as divine knowledge emanating from Brahma and considered very ancient. Even an uncompromising Western skeptic like Michael Witzel dates Atharvaveda to 1200 BC. Therefore, its antiquity is not in question.
For instance, the word Devapiyu meaning ‘abuser of Gods’ is mentioned in Atharvaveda 12.5.60 (Brahmagavi Sukta).
Here are the popular English scholarly translations by Sanskrit scholars of this word:
Ralph Griffith translates it as ‘Blasphemer of the Gods’. William Whitney translates it as ‘God-reviler’. Dr. Tulsi translates it as ‘reviler of Divinities’. There is a consensus here among all known English scholarly translations of Atharvaveda that Devapiyu means exactly the same as Devanindaka.
Even Vedamurti Acharya Sriram Sharma, the Vedic scholar who translated Atharvaveda into Hindi by relying on Sayanacharya’s sanskrit commentary, translates the aforesaid word as देवविरोधी (one who opposes Devas). Therefore, there is a consensus that Devaninda is indeed present in Vedas.
What was to be done to this ‘reviler of Gods’ and ‘Brahman wronger’? The following verses which include a prayer to Agni and the divine cow request the Gods to do the following to him:
O Cow, break thou the head of him who wrongs the Brāhmans,
criminal, niggard, blasphemer of the Gods.
Let Agni burn the spiteful wretch when crushed to death and slain by thee.
Rend, rend to bits, rend through and through, scorch and consume and burn to dust
PS: This is Griffith’s translation, but any other translation could be freely consulted and it would be seen that the Gist is the same.
I would like to caution beforehand that my comments do not pertain to the discussion of Astika/Nastika/Hinduism/Atheism at all. I currently do not have any opinion on that issue. This comment strictly pertains to ‘Devaninda’=abuse of Gods and the point made is that Devaninda is not tolerated by Vedas.