神兵精銳 Divine Weapons Show Their Keenness
逐句解 Line by line
The divine weapons show their keenness as the moment asks; the cinnabar vessel flowers, and is honoured wherever it goes.
神兵, divine weapons, is the phrase the chapter will use for the three arms right through to the closing lines. 丹器 is alchemical vocabulary again — the vessel in which cinnabar is refined — and 花生, flowers coming forth, is what the elixir is said to do when it is working. The poem keeps folding weapons and alchemy into the same image.
India stands high, yet still it disciplines the nature; the princes of Yuhua come home to the centre in the end.
The closing pair of lines names the place and the people, which is how these poems usually land. 戒性 is to keep the nature under precept — the disciplining of one's own character, which is what the princes are about to submit to. And 中, the centre, is the Earth position in the five-element scheme, so saying the princes come home to the centre puts them in the same diagram as the disciples. It also just means they come round.
Two lines to close, and both of them turn the display into a lesson. The weapons appear as needed, the elixir flowers, and the princes end up where they belong.
The last line is the one that matters for the story. Whatever the poem has been doing with elements and vessels, it finishes by saying that these three boys have been brought round, and the next scene is their father hearing about it.