Mahabharata 12.138.52

अमित्रं नैव मुञ्चेत ब्रुवन्तं करुणान्यपिदुःखं तत्र न कुर्वीत हन्यात्पूर्वापकारिणम्

amitraṃ naiva muñceta bruvantaṃ karuṇānyapiduḥkhaṃ tatra na kurvīta hanyātpūrvāpakāriṇam

Our plain-language meaning of this verse is waiting for scholar review.