Bhagavad Gita Chapter 6.5
uddhared ātmanātmānaḿ
nātmānam avasādayet
ātmaiva hy ātmano bandhur
ātmaiva ripur ātmanaḥ
Translation
One must deliver himself with the help of his mind, and not degrade himself. The mind is the friend of the conditioned soul, and his enemy as well.