瑜伽論記 7.440

7.440

或恐沈下時者謂知心羸劣恐沈沒時。於止觀品調柔正直等者，止觀均平名調柔正直。捨相，謂由所緣令心上捨等者，景云：極捨沈掉令心上捨，若太過精進則心浮動，為此不得太過精進。

Regarding "or when fearing sinking": this means knowing the mind is weak and fearing the time of sinking. Regarding "becoming supple and upright in the category of serenity and insight, etc.": serenity and insight being balanced is called supple and upright. Regarding "the characteristic of equanimity refers to causing the mind to have superior equanimity due to the focal object, etc.": Jing says: "Utterly abandoning sinking and agitation causes the mind to have superior equanimity; if one is overly energetic, then the mind is buoyant and agitated, and for this reason one must not be overly energetic."