tatah saptama akutyam
rucer yajno 'bhyajayata
sa yamadyaih sura-ganair
apat svayambhuvantaram
tatah—after that; saptame—the seventh in the line; akutyam—in the womb of Akuti; ruceh—by Prajapati Ruci; yajnah—the Lord's incarnation as Yajna; abhyajayata—advented; sah—He; yama-adyaih—with Yama and others; sura-ganaih—with demigods; apat—ruled; svayambhuva-antaram—the change of the period of Svayambhuva Manu.
The seventh incarnation was Yajna, the son of Prajapati Ruci and his wife Akuti. He controlled the period during the change of the Svayambhuva Manu and was assisted by demigods such as His son Yama.
The administrative posts occupied by the demigods for maintaining the regulations of the material world are offered to the highly elevated pious living beings. When there is a scarcity of such pious living beings, the Lord incarnates Himself as Brahma, Prajapati, Indra, etc., and takes up the charge. During the period of Svayambhuva Manu (the present period is of Vaivasvata Manu) there was no suitable living being who could occupy the post of Indra, the King of the Indraloka (heaven) planet. The Lord Himself at that time became Indra. Assisted by His own sons like Yama and other demigods, Lord Yajna ruled the administration of the universal affairs.

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