It is described there that one brahmana - he was a great devotee - he wanted to offer very brilliant service, arcana, in the temple worship. But he had no money. But some day he was sitting in a Bhagavataclass and he heard that Krishna can be worshiped even within the mind. So he took this opportunity because he was thinking since a long time how to worship Krishna very gorgeously, but he had no money.
So he, when he got this point, that one can worship Krishna within the mind, so after taking bath in the Godavari River, he was sitting underneath a tree and within his mind he was constructing very gorgeous simhasana, throne, bedecked with jewels and keeping the Deity on the throne, he was bathing the Deity with water of Ganges, Yamuna, Godavari, Narmada, Kaveri. Then he was dressing the Deity very nicely, then offering worship with flower, garland.
Then he was cooking very nicely, and he was cooking paramanna,sweet rice. So he wanted to taste it, whether it was very hot. Because paramanna is taken cold. Paramanna is not taken very hot. So he put his finger on the paramanna and his finger burned down. Then his meditation broken, because there was nothing. Simply within his mind he was doing everything. So... But he saw that his finger is burned. So he was astonished.
In this way, Narayana from Vaikuntha, He was smiling. Lakshmiji asked, "Why you are smiling?" "One of My devotee is worshiping like this. So send My men to bring him immediately to Vaikuntha."
So the bhakti-yoga is so nice that even if you have no means to offer the Deity gorgeous worship, you can do it within the mind. That is also possible.