Vivekachudamani 18

sadhananyatra catvari kathitani manashibhih |
yesu satsveva sannistha˜ yadabhave na sidhyati ||
(Sankaracarya's Vivekachudamani 18)

Great sages have spoken of four qualifications for attainment which, when present, succeed in the realization of Brahman and in the absence of which the goal is not attained.

There are thousands and thousands of literary men all over the world, and they have created many, many thousands of literary works for the information of the people in general for thousands and thousands of years. Unfortunately, none of them have brought peace and tranquillity on the earth. This is due to a spiritual vacuum in that literature; therefore the Vedic literature, especially the Bhagavad-gītā and the Śrīmad-Bhāgavatam are specifically recommended to suffering humanity to bring about the desired effect of liberation from the pangs of material civilization, which is eating the vital part of human energy. The Bhagavad-gītā is the spoken message of the Lord Himself recorded by Vyāsadeva, and the Śrīmad-Bhāgavatam is the transcendental narration of the activities of the same Lord Kṛṣṇa, which alone can satisfy the hankering desires of the living being for eternal peace and liberation from miseries.

As far as the duties of mankind are concerned, there are innumerable duties. Every man is duty-bound not only to his parents, family members, society, country, humanity, other living beings, the devas, etc. but also to the great philosophers, poets, scientists, etc. It is enjoined in the scriptures that one can relinquish all such duties and surrender unto the service of the Lord. So if one does so and becomes successful in the discharge of his devotional service unto the Lord, it is well and good. But it so happens sometimes that one surrenders himself unto the service of the Lord by some temporary sentiment, and in the long run, due to so many other reasons, he falls down from the path of service by undesirable association. There are so many instances of this in the histories. Bharata Mahārāja was obliged to take his birth as a stag due to his intimate attachment to a stag. He thought of this stag when he died. As such, in the next birth, he became a stag, although he did not forget the incident of his previous birth. Similarly, Citraketu also fell down due to his offenses at the feet of Śiva. But in spite of all this, the stress is given here to surrendering unto the lotus feet of the Lord, even if there is a chance of falling down because even though one falls down from the prescribed duties of devotional service, he will never forget the lotus feet of the Lord. Once engaged in the devotional service of the Lord, one will continue the service in all circumstances. In the Bhagavad-gītā, it is said that even a small quantity of devotional service can save one from the most dangerous position. There are many instances of such examples in history. Ajāmila is one of them. Ajāmila in his early life was a devotee, but in his youth, he fell down. Still, he was saved by the Lord at the end.