SB 11.12.24

evaṁ gurūpāsanayaika-bhaktyā
 vidyā-kuṭhāreṇa śitena dhīraḥ
vivṛścya jīvāśayam apramattaḥ
 sampadya cātmānam atha tyajāstram
Synonyms: 
evam — thus (with the knowledge I have given you); guru — of the spiritual master; upāsanayā — developed by worship; eka — unalloyed; bhaktyā — by loving devotional service; vidyā — of knowledge; kuṭhāreṇa — by the ax; śitena — sharp; dhīraḥ — one who is steady by knowledge; vivṛścya — cutting down; jīva — of the living entity; āśayam — the subtle body (filled with designations created by the three modes of material nature); apramattaḥ — being very careful in spiritual life; sampadya — achieving; ca — and; ātmānam — the Supreme Personality of Godhead; atha — then; tyaja — you should give up; astram — the means by which you achieved perfection.
Translation: 
With steady intelligence you should develop unalloyed devotional service by careful worship of the spiritual master, and with the sharpened ax of transcendental knowledge you should cut off the subtle material covering of the soul. Upon realizing the Supreme Personality of Godhead, you should then give up that ax of analytic knowledge.
Purport: 

Because Uddhava had achieved the perfection of personal association with Lord Kṛṣṇa, there was no need for him to maintain the mentality of a conditioned soul, and thus, as described here by the words sampadya cātmānam, Uddhava could personally serve the lotus feet of the Lord in the spiritual world. Indeed, Uddhava requested this opportunity at the beginning of this great conversation. As stated here, gurūpāsanayaika-bhaktyā: one can achieve pure devotional service by worshiping a bona fide spiritual master. It is not recommended here that one give up pure devotional service or one’s spiritual master. Rather, it is clearly stated by the words vidyā-kuṭhāreṇa that one should cultivate knowledge of the material world as described by Lord Kṛṣṇa in this chapter. One should fully understand that each and every aspect of the material creation is the expansion of the illusory potency of the Lord. Such knowledge works as a sharpened ax to cut down the roots of material existence. In this way, even the stubborn subtle body, created by the three modes of nature, is cut to pieces, and one becomes apramatta, or sane and cautious in Kṛṣṇa consciousness.

Lord Kṛṣṇa has clearly explained in this chapter that the cowherd damsels of Vṛndāvana were not interested in an analytical approach to life. They simply loved Lord Kṛṣṇa and could not think of anything else. Lord Caitanya Mahāprabhu taught that all His devotees should follow in the footsteps of the cowherd damsels of Vraja in order to develop the highest intensity of selfless love of Godhead. Lord Kṛṣṇa has elaborately analyzed the nature of the material world so that the conditioned souls, who are trying to enjoy it, can cut down the tree of material existence with this knowledge. The words sampadya cātmānam indicate that a person with such knowledge has no further material existence, because he has already achieved the Personality of Godhead. Such a person should not loiter in the kingdom of māyā, perpetually refining his understanding of the illusory creation. One who has accepted Lord Kṛṣṇa as everything may enjoy eternal bliss in the Lord’s service. Yet even though he remains in this world, he has no more business with it and gives up the analytical procedures for negating it. Lord Kṛṣṇa therefore tells Uddhava, tyajāstram: “Give up the ax of analytic knowledge by which you have cut down your sense of proprietorship and residence in the material world.”

Thus end the purports of the humble servants of His Divine Grace A.C. Bhaktivedanta Swami Prabhupāda to the Eleventh Canto, Twelfth Chapter, of the Śrīmad-Bhāgavatam, entitled “Beyond Renunciation and Knowledge.”