大般涅槃經義記 3.145

3.145

初中先喻，喻中，初至「名為淨田」喻明共住。眾僧如田，能生福故，殖福之人如似「田夫」，供僧生福如「種稻穀」，僧中惡行如似「䅎稗」，簡惡供善故名「芸除」，麁瞻似好名「肉眼觀」。「名為淨田至其成」下喻明久處，似穀之䅎、似稻之稗不可別故，至成方異，所況如是微惡難識，加以久處方知其別。

In the first, the analogy comes first. In the analogy, the beginning up to 'called a pure field' analogizes and clarifies living together. The Saṅgha is like a field because it can produce merit; the person cultivating merit is like a 'farmer'; making offerings to the Saṅgha to produce merit is like 'planting rice and grain'; evil conduct within the Saṅgha is like 'weeds and tares'; weeding out evil and offering to good is called 'weeding'; a coarse look seeming good is called 'observing with the flesh eye.' From 'called a pure field until its ripening...' onward analogizes and clarifies dwelling for a long time: weeds resembling grain and tares resembling rice cannot be distinguished, so only upon ripening do they become different; the point analogized is like this: subtle evils are difficult to recognize, and only by adding dwelling for a long time does one come to know their difference.