Psalm 91:2 (NKJV)
When you fly on an airplane, they show you where the exits are located. In buildings, you can find the emergency exits, which are not the normal way to leave the building, but they are the exits you will have to use in an emergency situation. Some buildings are listed as being shelters in a storm, or as the place to go if there is a tornado. All of these things are good and beneficial, but if you don't know where the exits and shelters are located, and how to get there, you can have a problem.
In Psalm 91 it talks about God's protection. God is talked about as our refuge and our fortress. A refuge is good, and a fortress is good, but if you don't know they exist, or how to get to the place of refuge, or the fortress, then you can have a problem. In Hosea 4:6, God said that "My people are destroyed for lack of knowledge". Some Christians do not even know about Psalm 91 and what God has said, and some believers think that it is up to God to protect us, if He wants to, otherwise we just suffer with our problems.
As Christians, we need to know and understand that God loves us so much, that He sent Jesus to die in our place and pay the price for our sin, so that we could live in a relationship with God. We need to know and understand all that God will do for us, and how He wants to help us in every situation. God has given us His Word and the Holy Spirit to show us what to do, and how to do it, in the time of trouble, so that when we face adversity that God can guide us into a place of refuge and be our fortress to protect and deliver us from whatever may come.