He himself will rescue you from the bird trap,
from the destructive plague.
⁴ He will cover you with his feathers;
you will take refuge under his wings.
His faithfulness will be a protective shield.
⁵ You will not fear the terror of the night,
the arrow that flies by day,
⁶ the plague that stalks in darkness,
or the pestilence that ravages at noon.
⁷ Though a thousand fall at your side
and ten thousand at your right hand,
the pestilence will not reach you.
⁸ You will only see it with your eyes 
and witness the punishment of the wicked.
⁹ Because you have made the Lord—my refuge,
the Most High—your dwelling place,
¹⁰ no harm will come to you;
no plague will come near your tent. Psalm 91:3-10

Wonderfully comforting passages there – God is our rescuer – and He will protect us as if we had a shield all around us. The terror at night and the arrow that flies at day – plagues and sicknesses and wars – when we are under the protection of God, we have nothing to fear.

Does this mean that bad things will never happen to us? Does this mean that we will never get sick during the middle of a plague or pestilence (or, pandemic – a word that wasn’t around during the time of the Psalms)? Does this mean we can be reckless with our lives and take big risks, and not worry about being wise, or taking precautions, because we are trusting in promises such as the one found in vs. 1:

¹¹ For he will give his angels orders concerning you,
to protect you in all your ways. ¹² They will support you with their hands
so that you will not strike your foot against a stone. Psalm 91:11-12

Does this passage mean, for instance, that we could climb up on top of a building and jump off, and trust that God will cause His angels to protect us and catch us?  Interestingly enough, that is a satanic thought – at least, similar thoughts about this passage caused Satan to tempt Jesus, using the very promises of this passage:

⁹ So [The Devil] took him to Jerusalem, had him stand on the pinnacle of the temple, and said to him, “If you are the Son of God, throw yourself down from here. ¹⁰ For it is written:

¹² And Jesus answered him, “It is said: Do not test the Lord your God.” Luke 4

This is interesting- here we have the devil taking a passage of Scripture and using it to try and get Jesus to do something wrong – in this case, to throw Himself down. Some have said that the temptation here is to get Jesus to show off, so to speak, and that would be wrong because showing off is wrong, but to that I would ask: Which is more impressive – surviving a jump off of the temple, or raising the dead? I’d say raising the dead is more impressive, and besides that – Jesus counters this temptation and this misuse of Scripture with another Scripture: DO NOT TEST THE LORD. So – we have this promise of protection that is wonderful in Psalm 91, and also wisdom from Jesus, which I think teaches us to not put God to the test by being foolhardy.

Here are some very encouraging Words from Spurgeon on this passage:

What is this terror? It may be the cry of fire, or the noise of thieves, or fancied appearances, or the shriek of sudden sickness or death. We live in the world of death and sorrow, we may therefore look for ills as well in the night-watches as beneath the glare of the broiling sun. Nor should this alarm us, for be the terror what it may, the promise is that the believer shall not be afraid. Why should he? Let us put it more closely, why should we? God our Father is here, and will be here all through the lonely hours; he is an almighty Watcher, a sleepless Guardian, a faithful Friend. Nothing can happen without his direction, for even hell itself is under his control. Darkness is not dark to him. He has promised to be a wall of fire around his people—and who can break through such a barrier? Worldlings may well be afraid, for they have an angry God above them, a guilty conscience within them, and a yawning hell beneath them; but we who rest in Jesus are saved from all these through rich mercy. If we give way to foolish fear we shall dishonour our profession, and lead others to doubt the reality of godliness. We ought to be afraid of being afraid, lest we should vex the Holy Spirit by foolish distrust. Down, then, ye dismal forebodings and groundless apprehensions, God has not forgotten to be gracious, nor shut up his tender mercies; it may be night in the soul, but there need be no terror, for the God of love changes not. Children of light may walk in darkness, but they are not therefore cast away, nay, they are now enabled to prove their adoption by trusting in their heavenly Father as hypocrites cannot do.

“Though the night be dark and dreary,
Darkness cannot hide from thee;
Thou art he, who, never weary,
Watchest where thy people be.”

C. H. Spurgeon, Morning and Evening: Daily Readings (London: Passmore & Alabaster, 1896).