Imagination is at the root of all fear and anxiety. If you were to place a plank on the ground and ask someone to walk along it, they would see no danger, and would not lose their balance as they traversed its length. However, if you were to suspend the plank one metre above the ground, they would probably hesitate. And if you placed the plank forty stories in the sky, spanning two skyscrapers, their answer would be a resounding "No!".
The physical situation is exactly the same in each case. It is still the same plank, and the risk does not increase with height. The factor that changes everything is the imagination. The imagination of falling off the plank is experienced as a reality, which paralyzes the mind with fear.
Fear is the mind killer. Yet fear is only imaginary, so is easy to destroy. A thief flees when found out. Darkness vanishes the moment the light is turned on.
A mind bathed in spirit is not within time, but time is within it. A boat is meant to go into water, but the water must not get into the boat. In the same way, we are meant to be in the world, but the world must not get into us.