In plain words
So those whose citta is fickle, whatever yāgas they perform, whatever kind of yogi they may be, may well appear in that form to the eyes of the world; but as far as the aim of the Ātma goes, as far as the inner aim goes, such a one can never be a true yogi, nor a true sādhaka, nor a person who truly listens. With this state of things in view, Nityānanda, the disciple of Śaṅkara, wrote this śloka. There are others who do their sādhanas either joined with society or leaving society. Living within society, the great souls Pōtarāju, Vēmana, Jayadēva, and such sacred people as Tukārām, Rāmakṛṣṇa Paramahaṃsa, Tyāgarāju, Gauraṅga, Kabīr and Rāmadāsu, all of them too, joined the company of others and went on giving this Ānanda to all through nāmasmaraṇa; these are the ones who have been dedicated within the principle of the Ātma. But there are some who, far from society, in some mountain cave, in some lonely place, in the Himālaya, keep their thoughts on God, develop the purity that befits their divine citta, and dedicate their lives to this aim of Brahman alone.
Three Kinds of Sādhana for a Steady Citta
Some others, in the midst of society, act like great devotees, put on various kinds of costume, and sit wherever a crowd gathers, wherever a crowd is watching, pretending to do dhyāna. Things like these can never be right practices for the spiritual path. Precious gems are put in a safe box and shown only to those who can buy them; no one sets out diamonds for sale in some bazaar, as fish are laid out in the fish market. Japa, dhyāna and all such things are like sacred jewels, like diamonds. They are only for those who, steady in citta in a solitary place, are to inquire there into the principle of Brahman; coming and sitting like an exhibition for a crowd to watch, or twirling the hands about somehow, is not right. Such things are merely like fish that give off a foul stench, and not like precious diamonds.