Offering gifts in charity, accepting charitable gifts, revealing one's mind in confidence, inquiring confidentially, accepting prasāda and offering prasāda are the six symptoms of love shared by one devotee and another.
In this verse Śrīla Rūpa Gosvāmī explains how to perform devotional activities in the association of other devotees. There are six kinds of activities: (1) giving charity to the devotees, (2) accepting from the devotees whatever they may offer in return, (3) opening one's mind to the devotees, (4) inquiring from them about the confidential service of the Lord, (5) honoring prasāda, or spiritual food, given by the devotees, and (6) feeding the devotees with prasāda. An experienced devotee explains, and an inexperienced devotee learns from him. This is guhyam ākhyāti pṛcchati. When a devotee distributes prasāda, remnants of food offered to the Supreme Personality of Godhead, in order to maintain our spirit of devotional service we must accept this prasāda as the Lord's grace received through the pure devotees. We should also invite pure devotees to our home, offer them prasāda and be prepared to please them in all respects. This is called bhuṅkte bhojayate caiva.
Even in ordinary social activities, these six types of dealings between two loving friends are absolutely necessary. For instance, when one businessman wishes to contact another businessman he arranges a feast in a hotel, and over the feast openly expresses what he wishes to do. He then inquires from his business friend how he should act, and sometimes presents are exchanged. Thus whenever there is a dealing of prīti, or love in intimate dealings, these six activities are executed. In the previous verse, Śrīla Rūpa Gosvāmī advised that one should renounce worldly association and keep company with the devotees (saṅga-tyāgāt sato vṛtteḥ). The International Society for Krishna Consciousness has been established to facilitate these six kinds of loving exchanges between devotees. This Society was started single-handedly, but because people are coming forward and dealing with the give—and—take policy, the Society is now expanding all over the world. We are glad that people are donating very liberally to the development of the Society's activities, and people are also eagerly accepting whatever humble contribution we are giving them in the shape of books and magazines dealing strictly with the subject matter of Kṛṣṇa consciousness. We sometimes hold Hare Kṛṣṇa festivals and invite life members and friends to participate in the feasting by accepting prasāda.