We can experience ananda perfectly in the association of Kṛṣṇa. We can associate with Kṛṣṇa as a servant, a friend, a father, a mother or a conjugal lover. There are five basic rasas – santa, dasya, sakhya, vatsalya and madhurya. In this material world, we experience the same rasas, or relationships. We are related to someone as a father, a son, a lover, a beloved, a master, a servant or whatever. These are perverted reflections of the relationship with Kṛṣṇa found in the spiritual world. Today in the material world I may be relishing my love for my son, but tomorrow my son may be my greatest enemy. There is no eternity in this kind of love. Or, if my son does not become my enemy, he may die. Today I may love some man or woman, but tomorrow we may break up. All of this is due to the defects of the material world. However, in the spiritual world, these relationships never break up. They simply increase and increase and this is called perfection.
Source: A.C. Bhaktivedanta Swami Prabhupada (2007 edition), “Teachings of Lord Kapila, The Son of Devahuti”, Page 180