My dear King, the conditioned soul, being in the bodily conception of life, considers his body to be his self and considers everything in relationship with the body to be his. Because he has this wrong conception of life, he is subjected to dualities like praise and chastisement.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
यन्निबद्धोऽभिमानोऽयं तद्वधात्प्राणिनां वधः । तथा न यस्य कैवल्यादभिमानोऽखिलात्मनः । परस्य दमकर्तुर्हि हिंसा केनास्य कल्प्यते
yannibaddho'bhimāno'yaṃ tadvadhātprāṇināṃ vadhaḥ | tathā na yasya kaivalyādabhimāno'khilātmanaḥ | parasya damakarturhi hiṃsā kenāsya kalpyate
SB 7.1.24