@reddust, I'm giving you big salute you coz you're covering Ten stages of Mahayana Bodhisattva path very speedy. This time nicely describe whole stage of no. nine. Buddha's lessons hasn't hide meanings. Every lessons has bet meanings and better to compare thoughts our life and then enter that into our soul. Sadhumati bhumi mentioned like as the proficient thoughts. Those stage indeed better thoughts for peaceful mind & holy wisdom.

In the ninth stage, the Bodhisattva addresses the ignorance of control of the intellectual powers and mental command of ultimate understanding of infinite expressions of truth, and the ignorance of free command of special knowledge of comprehension and communication.

That's point to understand much better what's ninth stage. Buddha gave through his teaching to Buddhists, controlling mindset methods and shown where's follower want to go using his holy wisdom. Buddha every time tried to bring final destination (Nirvana) Buddhists. Someone could pass Nibbana and someone false. But if We can pass to control mind via using controlling methods definitely find final destination.