Psalm 91 is frequently prayed in times of danger. But it opens with a very clear condition: “Whoever dwells in the secret place of the Most High”. Psalm 91:1 makes it perfectly clear that not everyone “will rest in the shadow of the Almighty.” Not every believer, but only those who dwell in God’s secret place.
We are so tuned to be active, get things done, work our to-do list, that we have become incapable to unwind and be calm. Yet in being calm in God's presence can be the source of the strength we need for our daily life.
If waiting on the LORD renews our strength, then why on earth do we keep running ahead of Him? We cannot stand unanswered prayer for too long, and since we like being in control, we take matters into our own hands. Maybe we give it a religious labelling (“I’m stepping out in faith”); while really we are fed up with waiting on God and try to push Him to start moving.