On Bhagavad Gita: Why do we swing between divinity and evil?

The following is an excerpt from a samvaad (dialogue) session with Acharya Prashant.

इदमद्य मया लब्धमिमं प्राप्स्ये मनोरथम् ।

इदमस्तीदमपि मे भविष्यति पुनर्धनम् ।। 16.13 ।।

idam adya mayā labdham imaṁ prāpsye manoratham