There is only one reason a Christian
would not experience peace–
he is not fully depending on God.
When we are not at peace,
it would be wise to figure out
who or what we are trusting in,
other than, or along with, God.
“You will keep him in perfect peace,
Whose mind is stayed on You,
Because he trusts in You.”
Isaiah 26:3 NKJV
Also: Philippians 4:4-7
