In the Eleventh Canto, 20th Chapter, 31st verse, of the Śrīmad-Bhāgavatam, Kṛṣṇa says, "My dear Uddhava, for persons who are seriously engaged in My service, the cultivation of philosophical speculation and artificial renunciation are not very favorable. When a person becomes My devotee he automatically attains the fruits of the renunciation of material enjoyment, and he gets sufficient knowledge to understand the absolute truth." That is the test of advancement in devotional service. A devotee cannot be in darkness because the Lord shows him special favor and enlightens him from within.
In the Eleventh Canto, 20th Chapter, 32nd and 33rd verses, of the Śrīmad-Bhāgavatam the Lord further instructs Uddhava: "My dear friend, the profits derived from fruitive activities, austerities, the culture of philosophical knowledge, renouncement, the practice of mystic yoga, charity and all similar auspicious activities are automatically achieved by My devotees—those who are simply attached to Me by loving service. These devotees have everything at their disposal, but they desire nothing outside of My devotional service. If ever a devotee should desire some material profit—to be promoted to the heavenly planets—or some spiritual profit—to go to the Vaikuṇṭhas—by My causeless mercy their desires are very easily fulfilled."
Actually a person who is developing Kṛṣṇa consciousness and still has some attachment to material enjoyment will soon be freed from such a tendency by regularly discharging devotional service under the instruction of a bona fide spiritual master.
Śrīla Rūpa Gosvāmī, then, recommends that one should not be attached to material sense enjoyment, but accept everything enjoyable which is in relationship to Kṛṣṇa. For example, eating is necessary, and one wants some palatable dishes to satisfy his sense of taste. So in that case, for the satisfaction of Kṛṣṇa rather than for the satisfaction of the tongue, some palatable dishes may be prepared and offered to Kṛṣṇa. Then it is renunciation. Let the palatable dishes be prepared, but unless they are offered to Kṛṣṇa one should not accept them for eating. This vow of rejecting anything which is not offered to Kṛṣṇa is actually renunciation. And by such renunciation one is able to satisfy the demands of the senses.
The impersonalists who try to avoid everything material may undergo severe austerities, but they miss the opportunity of being engaged in the service of the Lord. Thus their renunciation is not sufficient for perfection. There are many instances where, following such artificial renunciation without any contact with devotional service, the impersonalist again fell down and became attracted to the material contamination. There are many supposed renouncers even at the present moment who officially become sannyāsīs or renouncers and outwardly claim that spiritual existence is truth and material existence untruth. In this way, artificially they make a show of renunciation of the material world. However, because they cannot reach the point of devotional service, they fail to achieve the goal and again come back to material activities, such as philanthropic work, political agitation, etc. There are many instances of so-called sannyāsīs who gave up the world as untruth, but again came to the material world because they were not seeking their real repose at the lotus feet of the Lord.