Verse 3.15.3

अरिष्टं कोशं प्रपद्येऽमुनामुनामुना प्राणं प्रपद्येऽमुनामुनामुना भूः प्रपद्येऽमुनामुनामुना भुवः प्रपद्येऽमुनामुनामुना स्वः प्रपद्येऽमुनामुनामुना ॥ ३.१५.३ ॥

ariṣṭaṃ kośaṃ prapadye'munāmunāmunā prāṇaṃ prapadye'munāmunāmunā bhūḥ prapadye'munāmunāmunā bhuvaḥ prapadye'munāmunāmunā svaḥ prapadye'munāmunāmunā || 3.15.3 ||

3. For the sake of my child’s life, I take refuge in that immortal kośa [i.e., the chest, representing the universe]. For the sake of my child’s life, I take refuge in prāṇa [the vital breath]. For the sake of my child’s life, I take refuge in bhūh [the earth]. For the sake of my child’s life, I take refuge in bhuvaḥ [the mid-region]. For the sake of my child’s life, I take refuge in svaḥ [heaven].

Word-for-word explanation:

Amunā amunā amunā, for the sake of that [child’s life], for the sake of that [child’s life], for the sake of that [child’s life]; ariṣṭam kośam, in the immortal chest; prapadye, I take refuge; amunā amunā amunā, for the sake of that [child’s life—etc.]; prāṇam prapadye, I take refuge in prāṇa; amunā amunā amunā, for the sake of that [child’s life—etc.]; bhūḥ prapadye, I take refuge in bhūh [the earth]; amunā amunā amunā, for the sake of that [child’s life—etc.]; bhuvaḥ prapadye, I take refuge in bhuvaḥ [the mid-region]; amunā amunā amunā, for the sake of that [child’s life—etc.]; svaḥ prapadye, I take refuge in svah [heaven].

Commentary:

For the welfare of your child, surrender to every power on earth, in the mid-region, and in heaven. Repeat this three times, each time saying the name of the child thrice. Here the word amunā has been used instead of the name of the child.