The Rat who got liberation
Once, a rat was running on the altar of a Vishnu Deity, just at a time when one of the ghee lamps was about to go out. The rat thought that the flame might be some foodstuff, so he stuck his whiskers in it. The dying flame caught on to the rat's whiskers, and the fire flared up, catching on to the unused portion of the wick. In this way, by the rat's foolish sacrifice, the flame on Vishnu's altar continued to burn nicely. And for his service to Krishna, the rat went to Vaikuntha. This is the potency of devotional service to Krishna, even performed unknowingly.
Srila Prabhupada instructs:
Here is an example of giving service to the Supreme Personality of Godhead even without knowledge. Such service is called ajnata-sukrti. By such unknowing devotional service, one is favoured by the Supreme Personality of Godhead. Service rendered to the Supreme Lord, knowingly or unknowingly, never goes in vain.
Devotional service in Krishna consciousness is so sublime that even a little service rendered to Krishna, knowingly or unknowingly, gives one the greatest transcendental benefit. The system of worshipping Krishna by offering flowers from a tree is also beneficial for the living entity who is confined to the bodily existence of that tree. When flowers and fruits are offered to Krishna, the tree that bore them also receives much benefit, indirectly.
If a person renders loving service to Krishna, it never goes in vain. It is recorded in a spiritual account, and in due time it will fructify. This is confirmed in the Bhagavad-gita (2.40):
nehabhikrama-naso 'sti pratyavayo na vidyate
sv-alpam apy asya dharmasya trayate mahato bhayat
"In this endeavor there is no loss or diminution, and a little advancement on this path can protect one from the most dangerous type of fear."