(Purport to 9.30 continued)

Therefore a person who is situated in Krishna consciousness and is engaged with determination in the process of chanting Hare Krishna, Hare Krishna, Krishna Krishna, Hare Hare/Hare Rama, Hare Rama, Rama Rama, Hare Hare should be considered to be in the transcendental position, even if by chance or accident he is found to have fallen. The words sadhur eva, "he is saintly," are very emphatic. They are a warning to the nondevotees that because of an accidental falldown a devotee should not be derided; he should still be considered saintly even if he has fallen down accidentally. And the word mantavyah is still more emphatic. If one does not follow this rule, and derides a devotee for his accidental falldown, then he is disobeying the order of the Supreme Lord. The only qualification of a devotee is to be unflinchingly and exclusively engaged in devotional service.

The mark of a spot which may be seen on the moon does not become an impediment to the moonlight. Similarly, the accidental falldown of a devotee from the path of a saintly character does not make him abominable. On the other hand, one should not misunderstand that a devotee in transcendental devotional service can act in all kinds of abominable ways; this verse only refers to an accident due to the strong power of material connections. Devotional service is more or less a declaration of war against the illusory energy. As long as one is not strong enough to fight the illusory energy, there may be accidental falldowns. But when one is strong enough, he is no longer subjected to such falldowns, as previously explained. No one should take advantage of this verse and commit nonsense and think that he is still a devotee. If he does not improve in his character by devotional service, then it is to be understood that he is not a high devotee.

Translation and commentary by His Divine Grace A.C. Bhaktivedanta Swami Prabhupada

A devotee should still be considered saintly even if he falls down accidentally - BG 9.31