Chapter II sloka 58

yda s<hrte cay< kªmaeR=¼anIv svRz>,
#iNÔya[IiNÔyaweR=_yStSy à}a àitióta.

yad˜ saÕharate c˜yaÕ 
k¨rmo'ðg˜neeva sarvaþa× |
indriy˜õeendriy˜rthe'bhyas
tasya prajñ˜ pratish÷hit˜ ( 2|58)||

When, like the tortoise which withdraws on all sides its limbs, he withdraws his senses from the sense-objects, then his wisdom becomes steady.