अथैनामभिपद्यते अमोऽहमस्मि सा त्वम् ।सा त्वमस्यमोऽहम् ।सामाहमस्मि ऋक्त्वम् ।द्यौरहं पृथिवी त्वम् ।तावेहि संरभावहै सह रेतो दधावहै ।पुंसे पुत्राय वित्तय इति ॥बृह. ६,४.२० ॥
In plain words
Then he approaches her, saying: "I am ama, thou art sā; thou art sā, I am ama. I am the Sāman, thou art the Ṛc. I am the sky, thou art the earth. Come, let us two hold together; let us bring the seed together, for the getting of a male child."
The commentators
Bṛhadāraṇyakopaniṣadbhāṣyam· bhāṣya
अथैनामभिमन्त्र्य क्षीरौदनादि यथापत्यकामं भुक्त्वेति क्रमो द्रष्टव्यः । संवेशनकाले-- 'अमोऽहमस्मि' इत्यादि- मन्त्रेणाभिपद्यते ॥
In plain words
Then, having spoken the mantras over her, he gives her milk-rice and food of that kind, suited to the wish for a child; once she has eaten, the rest of the order follows as already described. At bedtime, he comes to her with the mantra that begins 'I am this...' and continues as before.
Close to the Sanskrit
Then, having consecrated her with mantras, [he gives her] milk-rice and the like, according to the desire for offspring; having eaten, the sequence is to be understood [thus]. At the time of retiring, he approaches [her] by the mantra beginning 'I am the amaḥ' and so on.