There is a famous story in the Upanishads which illustrates both the role and the power of work in spiritual practice and realisation. A youth approached a teacher to learn the spiritual truths of existence. The teacher handed over to him 2 head of cattle and said that he would take him up as a formal disciple when he returned with a herd of 1000 cattle. The youth went into the forest, living an isolated life, and focused on how to build the herd up, facing all the difficulties, obstacles and issues, both internal and external, over a number of years that it took to accomplish this feat. Eventually he returned with the requisite number and the teacher looked at him and asked him to take the seat of the teacher, and he would be the disciple! The teacher saw the radiance of the Eternal in the countenance of the youth, now turned into a realised seer of the Divine through his intensive sadhana through work.
Work done in the proper spirit, not to feed the ego or the vital desires, but as an offering to the Divine and for the purpose of carrying out the Divine purpose in the world, engages all the faculties of the being, mind, life and body to accomplish the action, and thereby incorporates at a deeper level than purely mental seeking or thought, the spiritual intensity and aspiration of the seeker. It brings together the powers of concentration, devotion and action in order to bear its fruit.
Sri Aurobindo writes: “Work is part of the Yoga and it gives the best opportunity for calling down the Presence, the Light and the Power into the vital and its activities; it increases also the field and the opportunity of surrender. … Yoga through work is the easiest and most effective way to enter into the stream of this Sadhana. … to quiet the mind and get the spiritual experience it is necessary first to purify and prepare the nature. This sometimes takes many years. Work done with the right attitude is the easiest means for that — i.e. work done without desire or ego, rejecting all movements of desire, demand or ego when they come, done as an offering to the Divine Mother, with the remembrance of her and prayer to her to manifest her force and take up the action so that there too and not only in inner silence you can feel her presence and working.”
Sri Aurobindo, Integral Yoga: Sri Aurobindo’s Teaching and Method of Practice, Chapter 6, Sadhana Through Work, Meditation and Love and Devotion, Work pp. 129-145