As a divinatory line, nine at the fifth place of Revolution reads within the hexagram's overall concern with believed in only once it is accomplished, great progress and success, advantage in being firm and correct, so that any occasion for repentance disappears. The line occupies a place proper to its own nature in the classical doctrine that odd places favour a firm, yang line and even places favour a yielding, yin line. It is also one of the two central lines of the hexagram, the place classical reading treats as the most balanced regardless of the line's own character. Its own text, that the great man produces his changes as a tiger changes its stripes, and before he has even consulted the oracle, faith is already placed in him, is the particular fortune assigned to this one stage of the situation, not to the hexagram as a whole.
The fifth line corresponds by classical convention with the second line, and the two correspond here, since one line is yin and the other yang. Read together with the trigram it belongs to, Dui in the upper position of the figure, the line marks the ruling stage of the hexagram, the place classical reading treats as its centre of authority, one stage in the six stage movement the hexagram traces from its first line to its last.
A change at this line, from yang to its opposite, is the mechanism the tradition uses to move from one hexagram to another. Flipping the fifth line of Revolution turns Dui into Zhen while the other trigram, Li, stays as it is, which yields Revolution's changing partner, Abundance (King Wen 55), the hexagram this line is recorded as transforming into.