An interesting transcript of a teaching that Lama Yeshe gave about the importance of doing retreat and the need for retreat centers. He mentions:

Why is retreat important? In order for our spirituality, pure morality, wisdom, single-pointed concentration and insight into reality to grow, we need time and space. The normal twentieth-century environment does not give us this. It induces either distraction or sluggishness, and retreat can take us beyond both. As human beings, we have the potential for unlimited growth, for limitless compassion and wisdom, bodhicitta and the six perfections. So retreat is very important in expediting this.

Furthermore, Dharma experiences come only when you put yourself into a Dharma situation. If you don’t immerse your body, speech and mind in Dharma, the Dharma can’t really be of use to you. So retreat is very important in promoting your development.

The first stage of your spiritual growth occurs during your first retreat. The second stage happens in your second retreat; the third stage in your third…and so on. Spiritual growth is not an intellectual thing. It has to be organic. It is beyond the intellectual; it has to become your own experience.

Let’s say you’re practicing a sadhana. If you’re just doing it at home without retreat or penetrative insight, you’re never going to become the sadhana. You’ll certainly never become the deity if you just do it that way.

You can see, even in European history, that Jesus and other great spiritual leaders went into solitary retreat. Christian, Muslim, Indian, Tibetan; all the great mahasiddhas went into isolation for certain periods and gained their high accomplishments through practicing intensively like that. So the history of human experience also shows that Dharma realizations come only through concentrated, twenty-four-hour-a-day practice.

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