Based on Bhagavad Gita Chapter 09, Text 02
The historical dating of spiritually significant events is often an exercise in irrelevance. Consider, for example, the mainstream academic opinion that characterizes bhakti as a cultural Indian movement that became widespread in medieval times.
Such a cultural and historical characterization of bhakti misses its essence. Gita wisdom indicates that bhakti correlates with the innate nature of the soul to love and serve the Supreme. It is thus present in the heart of all living beings at all places, east and west, and at all times, ancient, medieval, modern and post-modern.
Bhakti is the universal principle that underlies and unifies all the great religious traditions of the world. These traditions being centered as they are on adoring, worshiping and praising some manifestation of God like Christ, Allah or Buddha are essentially expressions of bhakti. They have some differences because the non-sectarian longing of the human heart for God is often expressed according to prevailing sectarian cultural norms. Also, this inner divine longing may be expressed less or more at different times in history depending on the receptivity or hostility of the prevailing sociopolitical circumstances. Yet beyond the variations in the form and frequency of its expression, bhakti remains a universal, eternal truth about the nature of the heart.