What’s the difference between Biblical meditation, allowing God to communicate with our spirit, and mysticism?

Rational thought is certainly of great value, but do we risk limiting God’s work in our life if we only engage Him with our mind, and not our spirit? How do we communicate with our spirit? Do we need to “disengage” our mind in order to not “get in the way” of spiritual communication?

These questions prompted me to look up some verses that may relate to spiritual communication.

Psalm 4:4 says, “reflect in your heart and be still” (HCSB).

Psalm 77:6 says, “I will meditate with my heart, and my spirit ponders” (NASB).

Ecclesiastes 1:16 says, “I communed with my heart” (NKJV).

Is this to say that there is a distinction between the mind and the heart?

In Ecclesiastes, I take it that he is saying that his mind is instructing his heart. He goes on to say, in the same verse, “My heart has understood great wisdom and knowledge.” We typically think of wisdom and knowledge as the realm of the mind, not the heart. Is Solomon using the mind and heart as synonyms? Some translations do not refer to the heart in this verse.

Psalm 46:10 says, “Be still, and know that I am God.” In what way are we to be still?

The context is that of fighting?; the command to be still is a command to stop worrying. See also Exodus 14:14 and Nehemiah 8:11.

Psalm 37:7 is another verse that says to “be still.” Again, the context is an instruction to not worry.