The Bhagavad Gita · Chapter 16 · verse 16.21
Three are the gates of this hell, destructive of the self — lust, anger, and greed. Therefore, abandon these three.
Sanskrit (Devanagari)
त्रिविधं नरकस्येदं द्वारं नाशनमात्मनः। कामः क्रोधस्तथा लोभस्तस्मादेतत्त्रयं त्यजेत्॥
Transliteration
tri-vidhaṁ narakasyedaṁ dvāraṁ nāśanam ātmanaḥ; kāmaḥ krodhas tathā lobhas tasmād etat trayaṁ tyajet
English translation
Three are the gates of this hell, destructive of the self — lust, anger, and greed. Therefore, abandon these three.
Meaning — what the verse is actually saying
The Gita is unusually direct here. Three forces above all others destroy the self: kāma (uncontrolled desire), krodha (anger), and lobha (greed). They are not subtle; they are not minor; they are not negotiable.
Modern practice — what to do today because of this
Pick whichever of the three is currently strongest in your life and target only that one for one month. Not all three. Just the dominant one. The Gita's assumption is that progress is local — you weaken whichever gate is open widest first.