Srimad-Bhagavatam: Canto 6 - Chapter 1 - Verse 44

Sanskrit:

सम्भवन्ति हि भद्राणि विपरीतानि चानघा: ।कारिणां गुणसङ्गोऽस्ति देहवान्न ह्यकर्मकृत् ॥ ४४ ॥

ITRANS:

sambhavanti hi bhadrāṇiviparītāni cānaghāḥkāriṇāṁ guṇa-saṅgo ’stidehavān na hy akarma-kṛt

Translation:

O inhabitants of Vaikuṇṭha, you are sinless, but those within this material world are all karmīs, whether acting piously or impiously. Both kinds of action are possible for them because they are contaminated by the three modes of nature and must act accordingly. One who has accepted a material body cannot be inactive, and sinful action is inevitable for one acting under the modes of material nature. Therefore all the living entities within this material world are punishable.

Purport:

The difference between human beings and nonhuman beings is that a human is supposed to act according to the direction of the Vedas. Unfortunately, men manufacture their own ways of acting, without reference to the Vedas. Therefore all of them commit sinful actions and are punishable.