sa tvaḿ mamaiśvarya-mada-plutasya
kṛtāgasas te 'viduṣaḥ prabhāvam
kṣantuḿ prabho 'thārhasi mūḍha-cetaso
maivaḿ punar bhūn matir īśa me 'satī
sah -- He; tvam -- Yourself; mama -- of me; aisvarya -- of rulership; mada -- in the intoxication; plutasya -- who is submerged; krita -- having committed; agasah -- sinful offense; te -- Your; avidushah -- not knowing; prabhavam -- the transcendental influence; kshantum -- to forgive; prabho -- O master; atha -- therefore; arhasi -- You should; mudha -- foolish; cetasah -- whose intelligence; ma -- never; evam -- thus; punah -- again; bhut -- may it be; matih -- consciousness; isa -- O Lord; me -- my; asati -- impure.
Although Lord Krishna protected the residents of Vraja by lifting Govardhana Hill, He had not yet punished Indra himself, and Indra feared that at any moment Sri Krishna 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 Krishna'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 Krishna 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 Krishna, and should not become entangled in the imperfect life of the material gods.