This (taking up of arms) was ordered by us to you for some special reasons before this. Then you had taken up your arms most fiercely and performed that unenviable deed (the extermination of the whole Kshatriya race).
इदं निमित्ते कस्मिंश्चिदस्माभिः प्रागुदाहृतम्। शस्त्रधारणमत्युगं तच्चाकार्यं कृतं त्वया॥