Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 13

Sanskrit:

आह चास्मान् महाराज प्रजाश्चाज्ञप्तुमर्हसि ।ययातिशापाद् यदुभिर्नासितव्यं नृपासने ॥ १३ ॥

ITRANS:

āha cāsmān mahā-rājaprajāś cājñaptum arhasiyayāti-śāpād yadubhirnāsitavyaṁ nṛpāsane

Translation:

The Lord told him: O mighty King, We are your subjects, so please command Us. Indeed, because of the curse of Yayāti, no Yadu may sit on the royal throne.

Purport:

Ugrasena might have told the Lord, “My dear Lord, it is actually You who should sit on the throne.” Anticipating this statement, Lord Kṛṣṇa told Ugrasena that because of Yayāti’s ancient curse, princes in the Yadu dynasty could technically not sit on the royal throne, and therefore Kṛṣṇa and Balarāma were disqualified. Of course, Ugrasena also could be considered part of the Yadu dynasty, but by the order of the Lord he could sit on the royal throne. In conclusion, these were all pastimes the Supreme Lord enjoyed as He played the part of a human being.