In the Hari-bhakti-sudhodaya there is a statement about the incense which is offered in the temple: "When the devotees smell the good flavor of the incense which is offered to the Deity, they thus become cured of the poisonous effects of material contamination, as much as one becomes cured of a snakebite by smelling the prescribed medicinal herbs." The explanation of this verse is that there is an herb found in the jungles which expert persons know how to use to revive the consciousness of one who is bitten by a snake. Simply by smelling that herb one becomes immediately relieved of the poisonous effects of the snakebite. The same example is applicable: when a person comes to visit the temple and smells the incense offered to the Deity, he is cured at that time from all his material contamination.
Any devotee coming into the temple should always offer something to the Deity-fruit, flowers, incense, etc. If one cannot offer anything in cash, something else must be offered. In India the system is that all the ladies and gentlemen who come in the morning to visit the temple bring so many things. Even one morsel of rice or one morsel of flour can be offered. It is a regulative principle that one should not go to see a saintly person or the Deity in the temple without any offering. The offering may be very humble, or it may be priceless. Even a flower, a little fruit, a little water-whatever is possible-must be offered. So when a devotee comes to offer something to the Deity in the morning, he is sure to smell the good flavor of the incense, and then at once he will become cleansed of the poisonous effect of material existence.
It is stated in the Tantra-sastra: "If the smell of the garland which was offered to the Deity in the temple enters into the nostril of a person, immediately his bondage to sinful activities becomes cleared. And even if one has no sinful activities, still, by smelling such remnants of flowers, one can advance from mayavadi (impersonalist) to devotee." There are several instances of this, a prime one being the advancement of the four Kumaras. They were impersonalist mayavadis, but after smelling the remnants of flowers and incense in the temple, they turned to become devotees. From the above verse it appears that the mayavadis or impersonalists are more or less contaminated. They are not pure.
It is confirmed in the Srimad-Bhagavatam: "One who has not washed off all reactions of sinful activities cannot be a pure devotee. A pure devotee has no more doubts about the supremacy of the Personality of Godhead, and thus he engages himself in Krsna consciousness and devotional service." A similar statement is in the Agastya-samhita: just to purify the impurities of our nostrils, we should try to smell the remnants of flowers offered to Krsna in the temple.

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