To some extent, we have already discussed this endurance of the results of transcendental work in the section on transcendental knowledge. The Personality of Godhead confirms this reality in the Bhagavad-gītā (6.40), and Ṭhākura Bhaktivinoda explains it in the following manner: "After all, the human race is divided into two sections. The one is legitimate and the other is illegitimate. Those who do not care about any laws of life, but simply work on the principle of sense gratification—they are all illegitimate. They may be civilized or uncivilized, they may be learned or illiterate, they may be powerful or weak, but such illegitimate persons, generally known as outlaws, always act like the lower animals. There is no good in them, in spite of all appearances. But those who are legitimate or law-abiding persons may be divided into three transcendental divisions: namely, the lawful workers, the empiric philosophers, and the transcendental devotees. The lawful workers are again divided into two sections: namely, the workers with a desire to enjoy the fruits of their work; and the transcendental workers, without any such desire. The worker with a desire to enjoy the fruits of his work is hankering after transient material happiness, and such a worker is rewarded with worldly or heavenly happiness within the material worlds. But it must be known that all these forms of happiness are temporary. Thus, the worker cannot attain to real happiness, which is permanent and transcendental. This real and transcendental happiness is attained only after liberation from the bondage of material existence. Any action which does not aim at such transcendental happiness is always temporary and baffling."
When ordinary work aims at such a transcendental objective, this work is called karma-yoga. By this process of karma-yoga, one gradually attains self-purification, then transcendental knowledge, next perfect meditation, and ultimately transcendental service to the Personality of Godhead. Sometimes a mundane worker is misunderstood to be a tapasvī (renunciant) or a mahātmā (great soul) because of the many austerities he performs to attain his mundane goals. But these austerities accepted by such rigid mundaners are, after all, aimed merely at material sense gratification, and therefore these austerities are useless in the transcendental sense. Some of the asuras, or demons, such as Rāvaṇa and Hiraṇyakaśipu, also underwent a severe process of austerity and penance, but they obtained nothing except some temporary objects of sensory pleasure. Therefore, only when one has transcended the limits of sensory pleasure can he be classified as a karma-yogī, or a worker for transcendental results. Real goodness lies in the activities of karma-yoga, even if one is only in the preliminary stages. Further, a karma-yogī makes progressive headway life after life, and this is confirmed as follows in the Bhagavad-gītā (6.43): "Even after successive births, the karma-yogī revives the transcendental sense of service, and by his natural attachment, he tries again to give further perfection to the progress of his transcendental activities."
Even if such transcendentalists slip away from the path of progress in some way or other, they are again given chances for making progress. As confirmed in Bhagavad-gītā (6.41), they are allowed to take their next birth either in the family of a bona fide brahmaṇa or in the family of a rich merchant who is devoted to the service of Godhead.
But among the transcendental mystics, variously classified as karma-yogīs, dhyāna-yogīs, jñāna-yogīs, haṭha-yogīs, and bhakti-yogīs, the last-named bhakti-yogīs are the greatest of all-because as again confirmed in Bhagavad-gītā (6.47), they are always absorbed in the thoughts and actions of transcendental loving service to Godhead.
Obviously, attainment of transcendental loving service to the Personality of Godhead is the ultimate goal of all mysticism. That is the purport of the above-mentioned verse. It is also worth mentioning the statement that Ṭhākura Bhaktivinoda makes in this connection: "The mystic who is engaged in the performance of the principle of loving service of Godhead is the highest of all mystics." One who renders loving service to Śrī Kṛṣṇa, the Personality of Godhead, with devotion and austerity, is the greatest of all mystics. Men who undertake austerities motivated by a desire for material results cannot be called yogīs or mystics. Those who are not motivated by material results include the empiric philosopher, the mystic pursuing the eightfold mystic perfections, and finally the mystic engaged in the transcendental loving service of the Personality of Godhead.
Factually, the mystic path is uniform and one. It is something like a series of stepping-stones to the highest goal. By accepting this path of mysticism, one becomes a pilgrim toward spiritual perfection. Work with transcendental results is the first stepping-stone on this transcendental path. When empiric philosophical deductions and a desire for renunciation are added, progress is made to the second stepping-stone. When one adds a definite conception of the supreme ruling principle, the Supreme Lord, one progresses to the third stepping-stone. And finally, when a process of transcendental loving service to the Supreme Personality is added, progress is made perfectly to the ultimate goal. The mystic path is therefore a transcendental evolution in which all the above stages are part of the gradual process of spiritual development. It is necessary to mention all the above stages to understand the final stage. Therefore, one who desires to attain to the supreme goal may adopt the systematic mystic path.