"Worries, if indulged, develop into idols. Anxiety gains a life of its own, parasitically infesting your mind." (31) What a sobering, morbid picture! No wonder we need to guard our thoughts. (Is. 26:3, Phil. 4:7) This requires "meta-cognition," the ability to think about what we are thinking about.
Even if we think we are blind to the habitual thought patterns of our own mind, God is not. I love David's prayer, "Search me, God, and know my heart; test me and know my anxious thoughts. See if there is any offensive, hurtful way in me; lead me in the everlasting way." (Ps. 139:23-24)
I am so grateful that God can read my mind and heal my heart! Each time I switch my thoughts into "the everlasting way," there is great rejoicing.