Bhagavad Gita 6.6 · BG 6.6
Chapter 6Verse 6
Dhyana Yoga
बन्धुरात्मात्मनस्तस्य येनात्मैवात्मना जितः। अनात्मनस्तु शत्रुत्वे वर्तेतात्मैव शत्रुवत्॥
bandhur ātmātmanas tasya yenātmaivātmanā jitaḥ, anātmanas tu śatrutve vartetātmaiva śatru-vat
Translation
For one who has mastered the mind, the mind is the best of friends; but for one who has not, it behaves like an enemy.
A mastered mind is your best friend. An unmastered one, your worst enemy.
What does this mean?
The same mind can work for you or against you. The difference is whether it's been trained or left to run unchecked.
In simple words
Krishna says the same mind is your best friend if you've mastered it and behaves like an enemy if you haven't. It's the same instrument either way. What decides which one you get is whether it's been trained or left to run loose.
The deeper idea
This follows directly from the previous verse about lifting yourself by your own mind. The claim is that the mind isn't neutral, it actively helps or actively undermines, and there's no third option of it just sitting there. An untrained mind doesn't stay still, it works against you, generating fear, distraction, and self-attack. Training it isn't about domination so much as no longer leaving your most powerful tool pointed at yourself.
How it applies to life
The same mind that can talk you through a crisis calmly, one step at a time, is the mind that at 3am builds elaborate catastrophes out of nothing. Same equipment, opposite effect. The difference is largely practice: attention you've trained to return to what's true and useful, versus attention left to wander wherever anxiety takes it. This verse frames that training as deciding whether the mind is on your side.