Psalm 91

He who dwells in the shelter of the Most High will rest in the shadow of the Almighty. I will say of the LORD, "He is my refuge and my fortress, my God, in whom I trust." Surely he will save you from the fowler's snare and from the deadly pestilence. He will cover you with his feathers, and under his wings you will find refuge; his faithfulness will be your shield and rampart. You will not fear the terror of night, nor the arrow that flies by day, nor the pestilence that stalks in the darkness, nor the plague that destroys at midday. A thousand may fall at your side, ten thousand at your right hand, but it will not come near you. You will only observe with your eyes and see the punishment of the wicked. If you make the Most High your dwelling--even the LORD, who is my refuge--then no harm will befall you, no disaster will come near your tent. For he will command his angels concerning you to guard you in all your ways; they will lift you up in their hands, so that you will not strike your foot against a stone. You will tread upon the lion and the cobra; you will trample the great lion and the serpent. 
"Because he loves me," says the LORD, "I will rescue him; I will protect him, for he acknowledges my name. He will call upon me, and I will answer him; I will be with him in trouble, I will deliver him and honor him. With long life will I satisfy him and show him my salvation."
Psalm 91


I've said before that christians lives are not going to be easy. You see, God implies that there will be difficult times, as he says, "I will be with him in trouble..." So there are times or trouble. It's easy to overlook those words and just think that life will be perfect. YES no harm or disaster will come near, YES you have an angel protecting you, but there WILL be trouble in your life.
My dictionary defines disaster as evilness or wrong doing. Ir's easy to take this psalm and say it's contradicting, but it's not. If disaster is something evil, God will not let evil be near you if you love God. But there will be trouble.
There's another part of this chapter to take into consideration. 


You will only observe with your eyes and see the punishment of the wicked.


What does God consider wicked? Sin? If you sin God will punish you. If you sin, I THINK God considers you wicked, but I KNOW God will forgive you. SOME trails you might be going through are punishment, but NOT ALL! Some are troubles.

I will deliver him and honor him.


DELIVER being the key word. In this case, delivering is rescuing, to release or save. If God is to deliver you, there has to be a problem.
So throughout this chapter, there are clues that the christian life will be hard, but God will be there. God will save you.


You will not fear the terror of night, nor the arrow that flies by day, nor the pestilence that stalks in the darkness, nor the plague that destroys at midday...For he will command his angels concerning you to guard you in all your ways; they will lift you up in their hands, so that you will not strike your foot against a stone.


Theses verse are the most miss leading. They can lead people to think that this chapter is contradicting. "You will not FEAR the terror of night..."
You will not be afraid of terror, but  there is terror. You will not FEAR the arrow, or the pestilence, or the plague. But it's there. You see God makes us courageous though we will not FEAR all these bad things, they will be there. If you " will say of the LORD, "He is my refuge and my fortress, my God, in whom I trust."" Then God will PROTECT you "his faithfulness will be your shield" and you will not fear. 


no harm will befall you, no disaster will come near your tent.


My dictionary also says disaster is misfortune, or bad luck. If God is testing you, is that bad luck? No! God is TEACHING you something. That is not bad luck! Disaster and hardships are different. VERY different! I already said harm is something evil or wrong. So have faith! God's faithfulness is what shields you from harm. Have faith that faithfulness will protect you! And don't let this Psalm fool you! God IS with you. God DOES shield you. God DOES deliver you when you pray. (He will call upon me, and I will answer him...)