These are nine standard modes of devotional service to the Lord, and a candidate can choose to adopt any one, two, three, four or all, however he likes. All the services rendered to the Absolute are in themselves absolute, with none of the quantitative or qualitative differences found on the material platform. On the spiritual platform everything is identical with everything else, although there is transcendental variegatedness. Emperor Ambarīṣa adopted all the above nine items, and he attained perfect success. It was he who engaged his mind on the lotus feet of the Lord, his voice in describing the spiritual world, his hands in cleansing the temple of the Lord, his ears in submissively hearing the words of Lord Śrī Kṛṣṇa, his eyes in viewing the Deities of the Lord, his body in touching the bodies of the devotees, his nostrils in smelling the flowers offered to the Lord, his tongue in tasting the food offered to the Lord, his legs in visiting the temple of the Lord, and all the energy of his life in executing the services of the Lord without in the least desiring his own sense gratification. All these activities helped him attain the perfect stage of life which defeats all dexterities of material science.
It is therefore important for all human beings to adopt these principles of spiritual realization for the perfection of life. A human being's only obligation is spiritual realization. Unfortunately, in modern civilization, human society is too busy in discharging national duties. Actually, national duties, social duties and humanitarian duties are obligatory only to those who are bereft of spiritual duties. As soon as a man takes his birth on this earth, not only does he have national, social and humanitarian obligations, but he also has obligations to the demigods who supply air, light, water, etc. He also has obligations to the great sages who have left behind them vast treasure-houses of knowledge to guide him through life. He has obligations to all kinds of living beings, to his forefathers, family members and so forth and so on. But as soon as one engages himself in the one single obligatory duty—the duty of spiritual perfection—then he automatically liquidates all other obligations without having to make separate efforts.