After moving to Utah and starting a new job I quickly began to have terrible times of private and public worship. In private worship my mind would dart all over the place, mostly back to work. In public worship my heart would easily harden and forfeit the grace available in assembled worship.
Through a bookstore sale I picked up a copy of A Remedy for Wandering Thoughts in the Worship of God. This old puritan work lives up to its title. It's not lengthy by puritan standards but brims with remarkable analogies and pointed statements that deeply convict and then comfort.
If you struggle to keep focused during worship, seek out the remedy here.