Canto 3 -
Araṇya-kāṇḍa
Chapter 66: Lakṣmaṇa Pacifies Śrī Rāma
Text 3.66.21

किं ते सर्वविनाशेन कृतेन पुरुषर्षभ।
तमेव त्वं रिपुं पापं विज्ञायोद्धर्तुमर्हसि॥

kiṁ te sarva-vināśena kṛtena puruṣa-rṣabha
tam eva tvaṁ ripuṁ pāpaṁ vijñāyoddhartum arhasi

kim = what is the use; te = of You; sarva-vināśena kṛtena = destroying everyone; puruṣa-ṛṣabha = O prince; tam eva = that; tvam = You; ripum = enemy [of Ours]; pāpam = sinful; vijñāya = after identifying; uddhartum = destroy him alone; arhasi = should.

O prince, what is the use of You destroying everyone? After identifying that sinful enemy [of Ours], You should destroy him alone.

[1] netrau netari bhedyavān. (Viśva)