Paramahaṁsa stage is the highest stage for a sannyāsī. A sannyāsī can beg from door to door just to collect food, but a paramahaṁsa who has taken ayācita-vṛtti, or ājagara-vṛtti, does not ask anyone for food. If someone offers him food voluntarily, he eats. Ayācita-vṛtti means being accustomed to refrain from begging, and ājagara-vṛtti indicates one who is compared to a python, the big snake that makes no effort to acquire food but rather allows food to come automatically within its mouth. In other words, a paramahaṁsa simply engages exclusively in the service of the Lord without caring even for eating or sleeping. It was stated about the six Gosvāmīs: nidrāhāra-vihārakādi-vijitau. In the paramahaṁsa stage one conquers the desire for sleep, food and sense gratification. One remains a humble, meek mendicant engaged in the service of the Lord day and night. Mādhavendra Purī had attained this paramahaṁsa stage.
Ref >> Srila Prabhupada Vani.