Śrīla Viśvanātha Cakravartī Ṭhākura says: evaṁ prahlādasyāṁśena sādhana-siddhatvaṁ nitya-siddhatvaṁ ca nāradādivaj jñeyam. There are two classes of devotees — the sādhana-siddha and the nitya-siddha. Prahlāda Mahārāja is a mixed siddha; that is, he is perfect partly because of executing devotional service and partly because of eternal perfection. Thus he is compared to such devotees as Nārada. Formerly, Nārada Muni was the son of a maidservant, and therefore in his next birth he attained perfection (sādhana-siddhi) because of having executed devotional service. Yet he is also a nitya-siddha because he never forgets the Supreme Personality of Godhead.

The word kuśalena is very important. One should live in the material world very expertly. The material world is known as the world of duality because one sometimes has to act impiously and sometimes has to act piously. Although one does not want to act impiously, the world is so fashioned that there is always danger (padaṁ padaṁ yad vipadām). Thus even when performing devotional service a devotee has to create many enemies. Prahlāda Mahārāja himself had experience of this, for even his father became his enemy. A devotee should expertly manage to think always of the Supreme Lord so that the reactions of suffering cannot touch him. This is the expert management of pāpa-puṇya — pious and impious activities. An exalted devotee like Prahlāda Mahārāja is jīvan-mukta; he is liberated even in this very life in the material body.