Here is another excerpt from Foster’s GREAT book: Celebration of Disciplines regarding our struggles with anxiety–
“As Jesus made clear in our central passage, freedom from anxiety is one of the inward evidences of seeking first the kingdom of God. The inward reality of simplicity involves a life of joyful unconcern for possessions….
Freedom from anxiety is characterized by three inner attitudes. If what we have we receive as a gift, and if what we have is to be cared for by God, and if what we have is available to others, then we will possess freedom from anxiety. This is the inward reality of simplicity. However, if what we have we believe we have gotten, and if what we have we believe we must hold onto, and if what we have is not available to others, then we will live in anxiety. Such persons will never know simplicity regardless of the outward contortions they may put themselves through in order to live “the simple life.” To receive what we have as a gift from God is the first inner attitude of simplicity.
To know that it is God’s business, and not ours, to care for what we have is the second inner attitude of simplicity. God is able to protect what we possess. We can trust him.
To have our goods available to others marks the third inner attitude of simplicity. If our goods are not available to the community when it is clearly right and good, then they are stolen goods. The reason we find such an idea so difficult is our fear of the future. We cling to our possessions rather than sharing them because we are anxious about tomorrow. But if we truly believe that God is who Jesus says he is, then we do not need to be afraid. When we come to see God as the almighty Creator and our loving Father, we can share because we know that he will care for us. If someone is in need, we are free to help them.
When we are seeking first the kingdom of God, these three attitudes will characterize our lives. Taken together they define what Jesus means by “do not be anxious.” They comprise the inner reality of Christian simplicity. And we can be certain that when we live this way the “all these things” that are necessary to carry on human life adequately will be ours as well.”