阿彌陀經疏 1.131

1.131

經曰：「周匝圍遶」，次釋第四國遍周圍也。《無量壽經》云：七寶諸樹周滿世界，國之四境及隨所在遶池遶舍，皆七重行樹及以欄楯。

The sūtra says: 'Completely surrounding them.' Next is the explanation of the fourth [point], surrounding the entire country. The Infinite Life Sūtra says: 'Trees of the seven jewels completely fill the world; at the four borders of the country and wherever one goes, encircling the ponds and encircling the dwellings, there are everywhere seven tiers of trees and balustrades.'