Comments

Comm. NT: 18.
Paṭhamajjhānakathāvaṇṇanā

It guards the line (gaṃ tāyati), thus it is lineage (gotta). When it occurs limitedly, it guards the naming (abhidhāna) and the recognition (buddhi) of the naming as restricted to a definite scope (ekaṃsa-visayatā).
For just as recognition does not take place without a meaning (attha) for its objective support (ārammaṇa), so naming (abhidhāna) does not take place without what is named (abhidheyya).
So it (the gotta) is said to protect and keep these.
But the limited should be regarded as the materiality peculiar to sense- sphere states, which are the resort of craving for sense desires, and destitute of the exalted (fine-material and immaterial) or the unsurpassed (supramundane).
The exalted lineage is explainable in the same way.

пали	Yañcettha sabbantimaṃ, taṃ parittagottābhibhavanato, mahaggatagottabhāvanato ca gotrabhūtipi vuccati.
Nyanamoli thera	And the last of these is also called “change- of-lineage” because it transcends the limited [sense-sphere] lineage and brings into being the exalted [fine-material-sphere] lineage. 18