大乘義章 13.77

13.77

次對道品辨其本末。如龍樹說，九想之觀開身念處，身念開導後三念處，以四念處開餘道品，以三十七品開涅槃門（此七門竟）。

Next, root and branch are distinguished in comparison to the factors of the path. As Nāgārjuna says, the contemplation of the nine notions opens up the application of mindfulness to the body; mindfulness of the body introduces and guides the subsequent three applications of mindfulness; through the four applications of mindfulness one opens up the remaining factors of the path; and through the thirty-seven factors one opens up the gate of nirvāṇa (this concludes the seventh section).