An anxious heart is always a divided heart.  Our souls grow anxious when we seek anything other than God’s Kingdom or when we attempt to have the Kingdom and… the Kingdom plus… the Kingdom with…

“NO ONE CAN SERVE TWO MASTERS FOR HE WILL HATE ONE AND LOVE THE OTHER.” Matthew 6:24

This speaks of the strain, worry and hate that comes from divided loyalties.  It is impossible to retain an allegiance to anything in addition to God.  If you have another equaled love - a mistress as well as the Lord - you do not even have the Lord. 
To love the Lord truly is to love Him completely, hating your other masters.
To have the Lord at all is to have Him fully and only. 
Anything beyond this is anxiety: the restless, worried mind of one caught in the deceptive tension of adultery.  One subtly aware of the loyalty due their spouse and the opposing disloyalty hidden in their hearts. One who can now never be fully at rest with either their first love or the other lover. 

2 things I’ve always quietly bristled against in the Christian faith begin to make perfect sense here:

1) The attribute of God’s jealousy.
2) The emphasis on purity. 

Perhaps He knows how He made us, perhaps He is aware at how restless we become outside His grasp, when we do not belong to Him alone.  Perhaps His jealously saves us from our anxiety (and is not just His ‘insecure’ need to exercise entitlement and intimidation…)  Both submission to God’s good and jealous heart and the pursuit of purity can be our only remedies when faced with the unease of our unfaithfulness.  Until we allow ourselves to be sifted of all mixture, of any particle that is not of Him, until we are free from impurity, our hearts cannot be still.  For it is in God and God alone we find His joy(in us), His light(in us), His rest(in us), His courage(in us).  Imagine the freedom of Peace in our hearts, and pure Peace in our hearts without all that we keep lurking beneath!

(c) Stephanie Diaz-Schumm