"Keep your heart with all diligence,
For out of it springs the issues of life." Proverbs 4:23

God looks at the heart, not at the mind or thoughts because those can be easily influenced by man factors and can not be trusted.

2 Chronicles 16:9 tells us,
"For the eyes of the LORD move to and fro throughout the earth that He may strongly support those whose heart is completely His."

There are other promises of His divine protection for the Believer as in the following:
"The angel of the LORD encamps around those who fear Him, And delivers them." Psalm 34:7 (Read this whole wonderful Psalm. The Psalmist here shows us that the LORD is our provider and deliverer.)

This Psalm is so glorious that I must quote a few more verses:
"Oh taste and see that the Lord is good;  Blessed is the man who trusts in Him." Vs. 8

"...There is no want to those who fear (revere and worship) Him." Vs. 9

"The eyes of the LORD are on the righteous, And His ears are open to their cry.
The face of the LORD is against those who do evil." Vs. 15-16

"The righteous cry out, and the LORD hears, And delivers them out of all their troubles." Vs. 17

"The LORD redeems the soul of His servants, And none of those who trust in Him shall be condemned." Vs. 22

Psalm 91 tells of the security of the one who trusts in the LORD. (Read all of this one, also.) "He shall cover you with His feathers.
And under His wings you shall take refuge; His truth shall be your shield and buckler." Vs. 4

"For He shall give His angels charge over you, To keep you in all your ways." Vs. 11

"As the mountains surround Jerusalem,
So the LORD surrounds His people
From this time forth and forever." Psalm 125:2

"'For I', says the LORD, 'will be a wall of fire around her (Jerusalem), and I will be the glory in her midst.'" Zechariah 2:5

SAFE AND SECURE!
"So we may boldly say:
'The LORD is my helper, I will not be afraid. What can man do to me?'"
Hebrews 13:6

The Apostle Peter repeats Psalm 34: 15-16 then follows it with, "And who is he who will harm you if you become follows of what is good?" 1 Peter 3:13 As seen in the above Scriptures, the answer is NONE!

All praise, honor and glory to the King of Glory, the Everlasting Father, Jehovah Jireh!
Amen