perseverance and devotion called for pursuit of knowledge,

विद्वानेव विजानाति विद्वज्जन परिश्रमम्।

न हि वन्ध्या विजानाति गुर्वीम् प्रसववेदनाम्।

vidvāneva vijānāti vidvajjana pariśramam|

na hi vandhyā vijānāti gurvīm prasavavedanām|

विद्वज्जन परिश्रमम् the extent of perseverance, the extent of work involve in their attempts by the learned persons

विद्वानेव विजानाति only a person with knowledge, a person in pursuit of knowledge understands

वन्ध्या a barren woman

गुर्वीम् प्रसववेदनाम् intense labour pains

न हि विजानाति do not understand indeed.

The extent of perseverance and devotion called for pursuit of knowledge, can be understood only by a person who has put his mind and body in pursuit of such enlightenment..

Only a woman who has given birth to a baby can know about the pains suffered during child birth.. This cannot be understood by a barren woman