Retreat is a very important time for us to pacify and filter out the dirt from our mind. Sometimes we think that it’s enough to meditate alone at home everyday. But it's not, because we may neglect and become lazy. Moreover, if we are connected with non-spiritual practitioners everyday, our mood, memory and the depth of our meditation will inevitably be influenced by that coarse atmosphere around us. So, occasional retreat is very beneficial to us. It does not only develop our wisdom, but also uplifts our spirit and body to an opener and happier level. That's why the Indians say: “It’s worthwhile to go to group meditation for two hours even if it requires forsaking hundreds of thousands of worldly tasks!” Let alone we forsake thousands of mundane matters to meditate together for dozens of hours or even 20 hours each day. This power and spiritual merits are more incredible .