"Six in the Fourth Place" down to "no praise." Zhengyi says: "Kua" means tying. A sack is used to store things, used here as a metaphor for the heart-mind storing wisdom. Closing up one's wisdom and not using it, hence it is said: "Tied sack."
Merit is not displayed to things, hence it is said: "No praise." Not coming into conflict with things, hence it is said: "No blame." Commentary on "Not engaging in yang affairs" down to "not the way of Peace."
Zhengyi says: As for "Not engaging in yang affairs, lacking the beauty of concealing brilliance": Six in the Third Place, being yin in a yang position, engages in yang affairs, but does not initiate affairs, waiting for the call before acting; since yang affairs remain, it says "concealing brilliance"—brilliance being the beauty of yang.
Now Six in the Fourth Place is yin in a yin position, with no yang affairs within; this is "not engaging in yang affairs, lacking the beauty of concealing brilliance." Facing a time of "closure and obstruction," it is a moment when "worthy people withdraw into obscurity."
Exercising caution is permissible, but it is not the way of prosperous peace.