Shloka 6.76.79
युद्धे अङ्गद-मैन्द-द्विविद-राक्षसयुद्धम्; कुम्भस्य प्रादुर्भावः तथा सुग्रीवेण पराभवः (Sarga 76: Angada and the Vanara chiefs battle Kampana, Prajaṅgha, Yūpākṣa, Śoṇitākṣa; Kumbha enters and is checked by Sugrīva)
उपालम्भभयाच्चापिनासिवीरमयाहतः ।कृतकर्मपरिश्रान्तोविश्रान्तःपश्यमेबलम् ।।।।
upālambhabhayāc cāpi nāsi vīra mayā hataḥ |
kṛtakarmapariśrānto viśrāntaḥ paśya me balam ||
O hero, I have not slain you, fearing I might later be reproached for striking you down while you were weary. Worn out by your exertions, you have paused to rest; now, after resting, behold my strength.
"O Stalwart! You have not been finished by me for the fear of reproaching. You are exhausted by your deeds and resting. Having rested, witness my strength now."
It reflects yuddha-dharma (ethics of battle): one should not take unfair advantage of an opponent who is exhausted or unable to fight properly, lest the victory become blameworthy rather than righteous.
In the Lanka war, Sugrīva taunts Kumbha during their combat, claiming he has not killed him yet because Kumbha appears fatigued; Sugrīva challenges him to recover and then witness Sugrīva’s power.
Maryādā (honourable restraint) in combat—strength guided by self-control and concern for righteous reputation.