楞伽阿跋多羅寶經註解 2.16

2.16

In the reply, stating that accomplishing four dharmas is the great skillful means indicates that while skillful means have many gates, these four dharmas are the greatest of skillful means, and thus different from other skillful means. Furthermore, these four do not go beyond cultivation, nature, cause, and fruit: that is, giving rise to cultivation entirely based on nature, proceeding from cause to fruit. The meaning of the four dharmas is explained below.