Many people are thinking, “I can enjoy this material world very nicely. Everyone is having such a good time. There is no reason I can’t enjoy myself as much as they.” This idea is an illusion because there is no real enjoyment in the material world. We may rise to a very high position like President Kennedy. We may be very good-looking, very famous, very intelligent, and well educated, very wealthy and very powerful, and we may have a very beautiful wife and children and hold the highest position in the country-but at any moment we are subject to be shot down. This is the nature of the material world: we have to face danger at every step. There is no question of having pleasure without impediments. Even when the pleasures are earned, they are earned after a great deal of struggle and sacrifice, and whatever pleasure may be acquired is temporary, for in the material world there is no pleasure that can give us constant and unending enjoyment. Only Krishna can give us that. Krishna is the Purusottama. The word purusa means “enjoyer.” The conditioned living entities are false enjoyers, imitation enjoyers. Here in this material world, all living entities are acting as purusas. The more exact meaning of purusa is “male.” The male is considered to be the enjoyer, and the female is considered to be the enjoyed. In the material world, whether one has a male or a female body, everyone has the propensity to enjoy, and therefore everyone is called purusa. But actually, the only purusa is the Supreme Lord. We living entities are His energy, and He is the supreme enjoyer. We are not purusa. Energies are employed for enjoyment, and we are energies, instruments of the Supreme Person. Therefore Purusottama is the supreme transcendental person, Krishna. When our pure devotion for the Supreme Personality of Godhead is employed and there are no impediments or stumbling blocks, that is the symptom of pure Krishna consciousness.
Source: A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “The Science of Self-Realization”, Page 338 & 350