2.58 And besides, yada, when; ayam, this one, the sannyasin practising steadfastness in Knowledge; samharate, fully withdraws; ['Fully' suggests absolute firmness in withdrawal, and 'withdraws' suggests full control over the organs] indriyani, the senses; indriya-arthhyah, from all the objects of the senses; iva, as; kurmah, a tortoise; sarvasah, wholly (withdraws); angani, its limbs, from all sides out of fear;   when the man engaged in steadfastness to Knowledge withdraws thus, then tasya, his; prajna, wisdom; pratisthita, remains established  (the meaning of this portion has already been explained).
As to that, [That is , so far as the phenomenal world is concerned.] the organs of a sick person, too, cease to be active when the refrains from sense-objects; they get fully withdrawn like the limbs of a tortoise. but not so the hankering for those objects. How that (hankering) gets completely withdrawn is being stated: