Picture two million people gathered on the banks of a river in India. It's the Kumbh Mela, the largest religious gathering on earth. Pilgrims from across the country have traveled here, many walking for weeks. At the auspicious moment determined by astrology, they surge into the water together.

Bodies press close. Hands rise in prayer. Voices chant mantras. The water churns with movement. For those few minutes, individual identity dissolves. Everyone is just a particle in a massive wave of devotion.

Later, pilgrims describe the experience as transcendent, overwhelming, unforgettable. They felt part of something infinitely larger than themselves. They felt, for that moment, the presence of the divine in and through the crowd.