Question: When did God first start to reveal Himself outwardly to human beings?

Sri Chinmoy: Thousands of years ago there lived the Vedic Seers. They prayed to God and meditated on God most soulfully and most devotedly. At that time God presented Himself to the Seers in a most beautiful, absolutely subtle, divinised human form. Although they were human beings, these Seers were able to see the subtle body of God. So 7,000 or 10,000 years ago, through the practice of spirituality the human consciousness was raised to the Himalayan height and people could see and feel God's Presence.

From:Sri Chinmoy,Niagara Falls versus children's rise, Agni Press, 1987
Sourced from https://srichinmoylibrary.com/nfv