The body fully engaged in Krishna’s service should not be neglected as material.

Srila Rupa Gosvami says:

prapancikataya buddhya hari-sambandhi-vastunah
mumuksubhih parityago vairagyam phalgu kathyate

“One who rejects things without knowledge of their relationship to Krishna is incomplete in his renunciation.” (Bhakti-rasamrta-sindhu 1.2.66) When the body is engaged in the service of the Lord, one should not consider the body material. Sometimes the spiritual body of the spiritual master is misunderstood. But Srila Rupa Gosvami instructs, prapancikataya buddhya hari-sambandhi-vastunah. The body fully engaged in Krishna’s service should not be neglected as material. One who does neglect it is false in his renunciation. If the body is not properly maintained, it falls down and dries up like an uprooted tree, from which flowers and fruit can no longer be obtained. The Vedas therefore enjoin:

om iti satyam nety anrtam tad etat-puspam phalam vaco yat satyam sahesvaro yasasvi kalyana-kirtir bhavita; puspam hi phalam vacah satyam vadaty athaitan-mulam vaco yad anrtam yad yatha vrksa avirmulah susyati, sa udvartata evam evanrtam vadann avirmulam atmanam karoti, sa susyati sa udvartate, tasmad anrtam na vaded dayeta tv etena.

The purport is that activities performed with the help of the body for the satisfaction of the Absolute Truth (om tat sat) are never temporary, although performed by the temporary body. Indeed, such activities are everlasting. Therefore, the body should be properly cared for. Because the body is temporary, not permanent, one cannot expose the body to being devoured by a tiger or killed by an enemy. All precautions should be taken to protect the body.

Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Eighth Canto, Chapter 19 – Text 40