These beings have also been called 'not divine' (a-deva) and 'not human' (a-miin~a), which shows that they were something between men and gods, i.e.,… - Kshetresa Chandra Chattopadhyaya

I have said above that the chief ground for placing the greater portion of the Rgveda-Samhita in a very early period is the archaic character of its language. But the Samhita is not lacking in late linguistic features as well. It well known that the word usura means "a good spirit", "a god" or "God" in the Rgveda-Samhiui as its cognate ahura means in the Avesta, and that in the later Vedic literature and in classical Sanskrit the word has undergone semantic deterioration, acquiring the sense of "demon".

Continuity of hieratic or bardic tradition preserves many old forms and in religious texts antique forms are generally preferred. ... The chief ground for taking the Rgveda-Samhita as the earliest Vedic. text is the archaic character of its language as compared with much of the remaining Vedic literature. Another ground for this conclusion is the fact that a large number of verses which are in their proper contexts in the Hymns of the Rgveda are found utilised in the mantra collections of the other Vedas, from which one may infer that they were borrowed from the Rgveda-Samhita. Both these grounds make the comparative antiquity of-large portions of the Rgveda-Samhita almost certain. But they do not entitle us to assume that the whole of the Rgveda- Samhita is older than the other Vedic texts .... Scholars have always recognised that this Samhita has older and later portions....

The name Varuna is not found outside India. Its equation with Greek Ouranos, though accepted by philologists, must be rejected on account of two differences, the quality of the second vowel and the place of the accent. The second vowel in Varuna is U and it is a in ouranos. The former word is accented on the first syllable and the latter on the final syllable, though accenting it on the syllable third from the end would not have militated against the special law about the place of the accent in the Greek language. Either discrepancy would not have by itself gone against the equation but their combination makes it extremely difficult to connect Varuna and Ouranos .... Varuna appears to be a purely Indo-Aryan word, formed in the same way as karuna, taruna, dharuna, etc.