Srimad Bhagavatam Canto 10, Chapter 27, Text 08

SB 10.27.8 

sa tvam mamaisvarya-mada-plutasya
 krtagasas te ’vidusah prabhavam
ksantum prabho ’tharhasi mudha-cetaso
 maivam punar bhun matir isa me ’sati
Engrossed in pride over my ruling power, ignorant of Your majesty, I offended You. O Lord, may You forgive me. My intelligence was bewildered, but let my consciousness never again be so impure.
Although Lord Krsna protected the residents of Vraja by lifting Govardhana Hill, He had not yet punished Indra himself, and Indra feared that at any moment Sri Krsna might call the son of Vivasvan, Yamaraja, who punishes impudent persons who defy the laws of God.
Indra was quite fearful and thus begged the Lord’s forgiveness on the plea that he could be purified only by Krsna’s mercy — that he was too stubborn to learn a good lesson through mere punishment.
In fact, despite Indra’s humility in this case, his heart was not completely purified. Later on in this canto we find that when Lord Krsna once took a parijata flower from Indra’s kingdom, poor Indra again reacted violently against the Supreme Personality of Godhead. Thus, we should aspire to go back to our eternal home in the kingdom of Krsna, and should not become entangled in the imperfect life of the material gods.
Srimad Bhagavatam Canto 10, Chapter 27, Text 07
Srimad Bhagavatam Canto 10, Chapter 27, Text 09