From 'The Xiang says: Modesty expressed in sound' to 'marching against one's own cities and domain.' The Zhengyi commentary states: 'The will is not yet attained' explains the meaning of 'modesty expressed in sound.'
The reason why it has only a vocal modesty and cannot engage in actual deeds to establish merit is that its dwelling is on the outside, and its aspiration to establish merit within has not yet been achieved.
'An army may be mobilized to march against one's own cities and domain' explains the purpose of mobilizing troops to campaign against one's domain.
Where the Classic says 'it is advantageous,' the Xiang Commentary replaces 'advantageous' with 'may,' meaning that although the internal aspiration is not yet achieved, one may still mobilize an army on the outside to campaign against one's towns and domain.
Regarding the note 'What prompts action springs from the pursuit of advantage': The Zhengyi commentary states: 'What prompts action springs from the pursuit of advantage' means that if ordinary people do not see advantage, their hearts are not moved.
Now the reason action arises is that seeing advantage prompts action; hence it says 'springs from advantage.'
'Where there is eating and drinking, there must be contention; where there is contention, multitudes must rise up' clarifies that it is for the sake of advantage that action occurs; action leads to contention, and contention leads to raising troops.
Thus the Sequence of Hexagrams says that Waiting represents eating and drinking, and where there is eating and drinking there must be contention; hence the hexagram of Waiting is followed by Conflict.
Contention inevitably raises troops; hence the hexagram of Conflict is followed by The Army.