A man giving way to grief delights his enemies and saddens his friends and himself becomes reduced in (strength). Therefore you should not grieve.
शोचन् नन्दयते शत्रून् कर्शयत्यपि बान्धवान्। क्षीयते च नरस्तस्मान्न त्वं शोचितुमर्हसि॥