What this hexagram is about
Water hidden within the earth — the image of raising an army. It speaks of leadership: the campaign must have a just cause, the commander must win the people's hearts, and only strict discipline can carry the day.
The Judgment 卦辞
师，贞，丈人吉，无咎。
Perseverance, and a seasoned leader, bring good fortune and no fault.
The Image 大象传
《象》曰：地中有水，师；君子以容民畜众。
Water gathers within the earth; so the noble person embraces the people and gathers a multitude.
Commentary on the Lines 小象传
师出以律，失律凶也。
The army marches by discipline; lose that discipline, and there is misfortune.
The Six Lines (hover over the figure above)
Six at the top大君有命，开国承家，小人勿用。
The great sovereign issues his commands, rewarding merit with lands and houses; but to the small-minded grant only goods, never weighty charge.
Six in the fifth place田有禽，利执言，无咎。长子帅师，弟子舆尸，贞凶。
When beasts ravage the fields, it is right to march out against them with just cause, and there is no fault. Let a steady elder lead, and it is well; let the incompetent meddle among them, and the army will return bearing its dead — to hold to this brings misfortune.
Six in the fourth place师左次，无咎。
The army, reading the moment, falls back and withdraws for a time; there is no fault.
Six in the third place师或舆尸，凶。
The army may return bearing its dead — misfortune; this comes of faulty command and the loss of men and officers.
Nine in the second place在师中，吉无咎，王三锡命。
Placed within the ranks and leading them well brings good fortune without fault; the sovereign, again and again, bestows praise and weighty commission.
Initial Six师出以律，否臧凶。
An army marching out must hold to strict discipline; where the orders are ill-kept, there is sure to be misfortune.