Valmiki Ramayana Ayodhya Kanda Sarga 62 Shloka 20
Original Shlokaएवं हि कथयन्त्यास्तु कौसल्यायाश्शुभं वचः। मन्दरश्मिरभूत्सूर्यो रजनी चाभ्यवर्तत।।2.62.20।।
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कौशल्यायाः of Kausalya, एवम् in that manner, शुभम् auspicious, वचः words, कथयन्त्याः speaking, सूर्यः the Sun, मन्दरश्मिः आभूत् faded rays, रजनी च night, अभ्यवर्तत had set in.
While Kausalya was speaking these hearttouching words, the rays of the Sun began to fade and the night fell.