The word prakrti means material nature, and purusa may also refer to the Supreme Personality of Godhead. If one wants to continue his association with prakrti, the female energy of Krsna, and be separated from Krsna by the illusion that he is able to enjoy prakrti, he must continue in his conditional life. If he changes his consciousness, however, and associates with the supreme, original person (purusam sasvatam), or with His associates, he can get out of the entanglement of material nature. As confirmed in Bhagavad-gita (4.9), janma karma ca me divyam evam yo vetti tattvatah: one must simply understand the Supreme Person, Krsna, in terms of His form, name, activities and pastimes. This will keep one always in the association of Krsna. Tyaktva deham punar janma naiti mam eti sorjuna: [Bg. 4.9] thus after giving up his gross material body, one accepts not another gross body but a spiritual body in which to return home, back to Godhead. Thus one ends the tribulation caused by his association with the material energy. In summary, the living entity is an eternal servant of God, but he comes to the material world and is bound by material conditions because of his desire to lord it over matter. Liberation means giving up this false consciousness and reviving ones original service to the Lord. This return to ones original life is called mukti, as confirmed in Srimad-Bhagavatam (muktir hitvanyatha rupam svarupena vyavasthitih).