Śrīmad-Bhāgavatam · Text 3.22.31
Who is speaking and story frame
कुशकाशमयं बर्हिरास्तीर्य भगवान्मनु: ।
अयजद्यज्ञपुरुषं लब्धा स्थानं यतो भुवम् ॥ ३१ ॥
kuśa-kāśamayaṁ barhir
āstīrya bhagavān manuḥ
ayajad yajña-puruṣaṁ
labdhā sthānaṁ yato bhuvam
Manu spread a seat of kuśas and kāśas and worshiped the Lord, the Personality of Godhead, by whose grace he had obtained the rule of the terrestrial globe.
Read Śrīla Prabhupāda's purport on Vedabase.io