I Ching, Yijing or Zhou Yi
"Oracle of the moon": © 2000 LiSe
Yi Jing, Oracle of the Moon

When Gěn changes to Lí, the sun rises over the mountains and the valleys receive its light. The darkness of night recedes, and everything becomes clear. Flowers lift their heads and spread their petals, people wake up, greet the sun and enjoy the energy and health the rays bring down. The world looks bright and new, the morning dew sparkles and the crisp air invites you to come out and start something.
The Mountain can give you rest and security. He is dependable, but he will not agree with anything that is not 'his thing'. Mountain is "manifested Earth". He takes that same earthly energy and imposes the same rules, but gives them definition in our immediate world. A mountain stops your path, forces you to look up, and provides a specific "place to be", providing a boundary that creates focus.
This is the short answer - click for the complete one with the spirit helpers.
About the 3 lines of the trigrams and the spirit helpers:
Each line, active or at rest, summons one of the 8 trigrams as a Helper. For an activated line: telling you what you need - or about a problem area or something to avoid.
For a stationary line: this is what you already have or do or what you don't need. Often we just need a reminder of our abilities. Or it could be what you wish or fear - but will not happen.
Active lines are the helpers to change things, they listen to intentions, which can come from you, surroundings, or fate. Stationary helpers are part of the core meaning, they are your soul talking, but they also see the impossibilities or what is lacking at the moment. They reinforce the overall power of a reading.