Liberated Person
One who acts to serve Krishna with his body, mind, intelligence and words is a liberated person, even within this material world.
One Should Always Remember
One should always remember that he is eternally a servant of Krishna. Whether one is engaged in material activity involving pounds, shillings and pence or is in the renounced order, he should always think that he is an eternal servant of God, for that is the real position of the living being. Taking Sanyasa and dealings in Pounds, shillings and pence are both external affairs. In any condition, one should always consider how to please and satisfy Krishna. Thus, even if one is involved in great material affairs, he will not become attached. As soon as one forgets that he is an eternal servant of Krishna, he becomes involved in material attachments. However, if one is always conscious that Krishna is always the Supreme master and that he is an eternal servant of Krishna, he is a liberated person in any condition. Entangling material activities will not affect him.
Serving Krishna With Great Love and Affection
A musician, because one has got a good attachment for music, he tries to perform it very perfectly. So love is the basis. Similarly, when you serve Krishna, if you have no love for Krishna, you cannot serve Him very nicely. Krishna also does not accept your service if it is not done in great love and affection.
Pure Devotees
A pure devotee is he who loves Krishna, without any material desire. Such pure devotees are very rare. Even if they have got some ulterior desire, that will be removed very soon, because they have taken to the pure process of Krishna Consciousness.