नियमेनैव as per rule, चरता while wandering (like an ascetic), नित्यशः always, काले काले at prescribed hours, त्रिः three times, अभिषेकः bathing, कार्यः will have to be done, तस्मात् therefore, वनम् life in the forest, दुःखतरम् is extremely difficult.

One has to wander about all the while (like an ascetic) as per the customs and take ablutions three times a day at prescribed hours. Hence life in the forest is extremely hard.