They traditionally believe that the word “yoga” was not used in Vedas, at least in the context of designating a system of esoteric psycho-practices as we know it today. However, this is not quite the case.
Vedas indeed do not contain the word “yoga” as an absolute equivalent of the meaning we assign to it now, notwithstanding the presence of numerous derivatives of the root-word “yuj”. Some scholars explain this by suggesting that yoga was first practiced by the Dravidian people from where it was borrowed by the Vedic Tradition. I believe this to be a simplifying assumption. Each culture has its own system of esoteric psycho-practices. Moreover, methods and concepts of these systems that seem to be totally different at first glance are in any case adjacent in virtue of their having a single object – the human mind. Fusion of cultures is naturally followed by fusion of systems bringing a result that may be very quaint in form. Thus it whould be quite correct to speak about the “proto-yoga” of Vedas. You may find more details in my public lecture.
However, my confidence as to the absence of references to yoga in Vedas has wavered recently, after I’d come to know about a very interesting hymn from Atharvaveda. Let me remind that Atharvaveda was a collection of texts that we would today call a “spell of magic” and that were used mainly for solving different applied problems.
Here is the hymn text:
índrasyaúja stʰéndrasya sáha stʰéndrasya bálaṃ stʰéndrasya vīryà1ṃ stʰéndrasya nr̥mṇáṃ stʰa /
jiṣṇáve yógāya brahmayogaír vo yunajmi //1//
índrasyaúja stʰéndrasya sáha stʰéndrasya bálaṃ stʰéndrasya vīryà1ṃ stʰéndrasya nr̥mṇáṃ stʰa /
jiṣṇáve yógāya kṣatrayogaír vo yunajmi //2//
índrasyaúja stʰéndrasya sáha stʰéndrasya bálaṃ stʰéndrasya vīryà1ṃ stʰéndrasya nr̥mṇáṃ stʰa /
jiṣṇáve yógāyendrayogaír vo yunajmi //3//
índrasyaúja stʰéndrasya sáha stʰéndrasya bálaṃ stʰéndrasya vīryà1ṃ stʰéndrasya nr̥mṇáṃ stʰa /
jiṣṇáve yógāya somayogaír vo yunajmi //4//
índrasyaúja stʰéndrasya sáha stʰéndrasya bálaṃ stʰéndrasya vīryà1ṃ stʰéndrasya nr̥mṇáṃ stʰa /
jiṣṇáve yógāyāpsuyogaír vo yunajmi //5//
índrasyaúja stʰéndrasya sáha stʰéndrasya bálaṃ stʰéndrasya vīryà1ṃ stʰéndrasya nr̥mṇáṃ stʰa /
jiṣṇáve yógāya víśvāni mā bʰūtā́ny úpa tiṣṭʰantu yuktā́ ma āpa stʰa //6//
agnér bʰāgá stʰa apā́ṃ śukrám āpo devīr várco asmā́su dʰatta /
prajā́pater vo dʰā́mnāsmaí lokā́ya sādaye //7//
índrasya bʰāgá stʰa apā́ṃ śukrám āpo devīr várco asmā́su dʰatta /
prajā́pater vo dʰā́mnāsmaí lokā́ya sādaye //8//
sómasya bʰāgá stʰa apā́ṃ śukrám āpo devīr várco asmā́su dʰatta /
prajā́pater vo dʰā́mnāsmaí lokā́ya sādaye //9//
The approximate translation sounds as follows:
The Glow (ojas) of Indra, the Power of Indra, the Valor (virya) of Indra, the Manhood of Indra
For victorious yoga (unity) by means of Brachman’s unity I unite with you
The lines then repeat so that “Brachman’s” uniting element is replaced by “Kshatriya’s” “Indra’s”, “moon’s” and so on.
As you can guess, the root yuj (the one the word “yoga” stems from) and its derivatives is trice played on in the second line of each verse. The words that I have translated as “yoga” can be interpreted as “unity”, and this shall be also a correct variant. As we remember from this article, there are three types of word meaning formation in Sanskrit.
But the hymn under consideration is also interesting due to the suggestion that it may be a “missing link” in development of the term “yoga” into a separate title of a practice or a state. Of the one hand, the practice presented in the verse bears an expressively magic character, it involves energy and is related to “conjunction” with power of a deity, “transmitting” it through the self, and this is the practice that we refer to as yoga. Of the other hand, the explanation of yoga as “merger” with a transcendental principle can be found in dozens of later texts.