Valmiki Ramayana Yuddha Kanda Sarga 59 Shloka 142

त्वया by you, सुभीमम् exceedingly difficult, महत् great, कर्म task, कृतम् done, त्वया by you, अहम् I, हतप्रवीरः mighty heroes killed, कृतःच done, तस्मात् therefore, परिशान्तःइति exhausted, व्यवस्य declare, त्वाम् you, मृत्युवशम् to death, ननयामि not sent.

A great task of killing mighty heroes has been accomplished by you. Therefore, you are exhausted. I declare that I will not send you to death.