There are Four Paths of Yoga: Karma Yoga, the path of service; Bhakti Yoga, the path of love; Raja Yoga, the path of Ashtanga, or the Eight Limbs of Yoga; and Jnana Yoga, the path of knowledge. The path of knowledge does involve study: study of sacred texts and study to gain knowledge of life and existence. This path of knowledge and study will be different for each of us. For the Buddha, it was contemplating and meditating on suffering. For Einstein, it was through the study of physics.
Every one who is seriously involved in the pursuit of science becomes convinced that a spirit is manifest in the laws of the Universe-a spirit vastly superior to that of man, and one in the face of which we with our modest powers must feel humble.
– Albert Einstein
Whatever path we take towards knowledge, the ultimate goal is to attain knowledge of our timeless and True Self, or Atman, and to achieve the understanding of the expansive and ultimate reality of Brahman, the Universe and Absolute Oneness of All. Realization of Atman is knowledge that we are not our bodies and minds, but souls on a journey towards union, or yoga, with All.
The Self is the sun shining in the sky, the wind blowing in space; he is the fire at the altar and in the home the guest; he dwells in human beings, in gods, in truth, and in the vast firmament; he is the fish born in water, the plant growing on earth, the river flowing down from the mountain. For the Self is supreme!…The Self is the light reflected by all.
– Yama, the god of death, Katha Upanishad