In the beginning was the Word
And the Word was with God
And the Word was God.
[Written circa 50-100 AD]
Prajapatir vai idam agre asit
Tasya vag dviitiya asit
Vag vai paraman Brahman
In the beginning was Prajapati (Brahman)
With whom was the Word;
And the Word was verily Brahman.
[Lila: Brahman and Prajapati both mean God, the former in his utterly transcendent and immanent form and the latter in his form as creator of the world.]
(Krishna Yajurveda, Kathaka Samhita, 12.5, 27.1; Krishna Yajurveda, Kathakapisthala Samhita, 42.1; Jaiminiya Brahmana II, Samaveda, 2244
Approximate date: 1000-1200 BC, with a strong possibility from internal evidence, of being even earlier.