Canto 2 -
Ayodhyā-kāṇḍa
Chapter 25: Kausalyā Invokes Auspiciousness for Rāma
Text 2.25.32

यन्मङ्गलं सहस्राक्षे सर्वदेवनमस्कृते।
वृत्रनाशे समभवत्तत्ते भवतु मङ्गलम्॥

yat maṅgalam = auspiciousness; sahasra-akṣe = upon the thousand-eyed Indra; sarva-deva-namaskṛte = who was honored by all the devas; vṛtra-nāśe = upon the destruction of Vṛtra; samabhavat =  invoked; tat = the; te = upon You; bhavatu maṅgalam = may be invoked.

May the auspiciousness invoked upon the thousand-eyed Indra, who was honored by all the devas upon the destruction of Vṛtra, be invoked upon You!1 


1 The significant history of Vṛtrāsura is elaborated by Śrīla Śukadeva Gosvāmī in Chapters 7 to 17 of Canto 6 of Śrīmad-Bhāgavatam.