Valmiki Ramayana Ayodhya Kanda Sarga 23 Shloka 17
Original Shlokaदैवं पुरुषकारेण यः समर्थः प्रबाधितुम्। न दैवेन विपन्नार्थः पुरुषस्सोऽवसीदति।।2.23.17।।
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यः पुरुषः such a man, पुरुषकारेण with human effort, दैवम् destiny, प्रबाधितुम् to strike, समर्थः is capable, सः he, दैवेन by destiny, विपन्नार्थः with defeated objectives, न अवसीदति will not grieve.
In the case of one capable of striking destiny with human efforts it cannot defeat his objective and bring him despondency.