Choosing to trust God is not an excuse for inactivity. It is not a license to passively surrender responsibility because God is going to take care of things. Choosing to trust God is a decision to meet Him in the harmony of mutual action.
The Israelites took the situation that they were in and surrendered it to God, trusting that He would work through the circumstances that they were in.
As the people experienced the renewal of their relationship with God, they made a decision to renew their commitment to be faithfully obedient to that relationship as well.