durdharṣaḥ — unconquerable; tejasā — by prowess; iva — like; agniḥ — fire; mahā-indraḥ — the King of heaven; iva — likened; durjayaḥ — insuperable; titikṣayā — by tolerance; dharitrī — the earth; iva — like; dyauḥ — the heavenly planets; iva — like; abhīṣṭa-daḥ — fulfilling desires; nṛṇām — of human society.

Translation

“Mahārāja Pṛthu was so strong and powerful that no one could disobey his orders, any more than one could conquer fire itself. He was so strong that he was compared to Indra, the King of heaven, whose power is insuperable. On the other hand, Mahārāja Pṛthu was also as tolerant as the earth, and in fulfilling various desires of human society, he was like heaven itself.”

Bhaktivedanta Purport

By Śrīla Prabhupāda

It is the duty of a king to give protection to the citizens and to fulfill their desires. At the same time, the citizens must obey the laws of the state. Mahārāja Pṛthu maintained all the standards of good government, and he was so invincible that no one could disobey his orders any more than a person could stop heat and light emanating from a fire. He was so strong and powerful that he was compared to the King of heaven, Indra. In this age modern scientists have been experimenting with nuclear weapons, and in a former age they used to release brahmāstras, but all these brahmāstras and nuclear weapons are insignificant compared to the thunderbolt of the King of heaven. When Indra releases a thunderbolt, even the biggest hills and mountains crack. On the other hand, Mahārāja Pṛthu was as tolerant as the earth itself, and he fulfilled all the desires of his citizens just like torrents of rain from the sky. Without rainfall, it is not possible to fulfill one’s various desires on this planet. As stated in Bhagavad-gītā (3.14), parjanyād anna-sambhavaḥ: food grains are produced only because rain falls from the sky, and without grains, no one on the earth can be satisfied. Consequently, an unlimited distribution of mercy is compared to the water falling from the clouds. Mahārāja Pṛthu distributed his mercy incessantly, much like rainfall. In other words, Mahārāja Pṛthu was softer than a rose flower and harder than a thunderbolt. In this way he ruled over his kingdom.