As a divinatory line, six at the sixth place of Obstruction reads within the hexagram's overall concern with advantage found in the southwest, and the contrary in the northeast, advantage in seeing the great man, and in being firm and correct. 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. Its own text, that going forward leads to difficulty, remaining still brings great merit, good fortune, advantage in seeing the great man, is the particular fortune assigned to this one stage of the situation, not to the hexagram as a whole.
The sixth line corresponds by classical convention with the third line, and the two correspond here, since one line is yin and the other yang. Read together with the trigram it belongs to, Kan in the upper position of the figure, the line marks the far edge of the hexagram, past the point the ruling fifth line governs, one stage in the six stage movement the hexagram traces from its first line to its last.
A change at this line, from yin to its opposite, is the mechanism the tradition uses to move from one hexagram to another. Flipping the sixth line of Obstruction turns Kan into Xun while the other trigram, Gen, stays as it is, which yields Obstruction's changing partner, Development (King Wen 53), the hexagram this line is recorded as transforming into.