Whatever the historical context of this psalm of David, the times are troubling. David seems quiet in his thoughts and confident in his trust. May we be encouraged by his testimony.
David’s confidence begins with remembrance. “You have given me relief when I was in distress” (v. 1). It is sweet to look back and remember God’s loving-kindness in our lives. Especially when my soul is heavy, I pick up my journal and remember the times God has delivered me from evil. I thank Him again for past deliverance and rest peacefully assured of future relief.
David’s confidence continues in prayer—that God “hears when [he] call[s] to Him” (v. 1,3). Admittedly, there are times when it seems God doesn’t hear my prayer. In this case, the problem lies with me, not God. Psalm 91 asserts that God answers the one who holds fast to Him in love (vv. 14,15). Indeed, God hears the prayer of the godly and answers them according to His will. So, we may be completely confident in our prayers when we submit to His sovereignty (Matthew 6:10; cf. 28:18), obey His command (John 14:15), and pursue His will (Matthew 6:33).
David also trusts in God to bring him gladness, peace, and safety (v. 7,8). It’s not hard to be happy when we have everything we desire or when everything goes our way. But a light heart seems unattainable when life seems to be a series of catastrophes, disappointments, or unfortunate events. Still, Jesus teaches that believers are blessed amid persecution, specifically for the sake of righteousness and because of Him (Matthew 5:10-12).
I am reminded of the apostles’ persecution in Acts 5. The Sanhedrin wanted to kill them. Enter Gamaliel’s counsel—if this rising is of men, it will fail, but if of God not only will it succeed, but you might be found opposing God (Acts 5:35-39). So, the apostles were flogged and released. Bloody and in agonizing pain, they left rejoicing that they were counted worthy to suffer dishonor for the name of Christ. Peter later writes, “if anyone suffers as a Christian . . . let him glorify God in that name . . . [and] entrust their souls to a faithful Creator while doing good” (1 Peter 4:16,19). 
It’s a kind of certificate of authenticity, being persecuted or suffering for Christ. When we endure it, we can look it square in the eye, smile, and say, “Great is our reward in heaven” because as surely as the heavens are above the earth, Jesus will return to take us there (John 14:3). And that makes me glad, indeed. That joy of the Lord gives me strength to be at peace with my enemies, pray for them, and overcome evil with good (Matthew 5:43-48; Romans 12:9-21).
Nothing is more comforting to me than the security of God’s faithfulness. Remember that “faithful Creator” Peter talked about in 1 Peter 4? He says of Him in 1 Peter 5:10—“And after you have suffered a little while, the God of all grace . . . will himself restore, confirm, strengthen, and establish you.” That is security, peace, and joy that help me go to sleep at night, wake up refreshed, and live another day as a child of God for the glory of God. To Him be the glory forever and ever. Amen.

Scholars have titled this psalm “The Lord Helps His Troubled People,” “Morning Prayer of Trust in God,” “Save Me, O My God,” and others. David wrote this psalm “when he fled from Absolom, his son.” The historical reference is to 2 Samuel 15, though you may choose to read chapters 13-18 (or more) for more complete context. If I were in David’s shoes, the rebellion of my son would cause me fantastic physical, emotional, intellectual, and spiritual distress. So, what does the Lord’s anointed do in such times of trouble?
He prays. He humbles himself under the mighty hand of God and cries aloud, “O Lord, my God.” Though his adversaries, with their voices, defy God (v. 2), with his voice, he exalts God.
In his solitude with God, he acknowledges his deliverance in three ways. The Lord is our shield. He protects every part of us: heart, soul, mind, and body. He is our glory because we know him, belong to Him, claim His promise of salvation, and conform to Christ. And He is the lifter-up of our heads. The idea is that God enables us to rise and overcome our troubles and smile back at them. James writes, “Count it all joy, my brothers, when you meet trials of various kinds, for you know that the testing of your faith produces steadfastness” (James 1:2,3). Whether we sink in times of trouble or rise depends on our faith and prayer. God wants to help us smile on our problems, but if we do not seek His help, it will not come.
Despite his adversaries and trouble, David could still lie down and sleep. Fearlessly he rested, calmed by Divine peace. When he awoke, Divine courage emboldened him to be unafraid of thousands. Undoubtedly, answered prayers of the past gave him confidence in future prayers. All that remained was for the battle to play out.
How often do we find ourselves in trouble? I dare say daily. When in troubling times, let us follow David’s example. When we encounter trials of various kinds, let us humble ourselves before God in prayer and ask for help to smile upon our trouble and consider it pure joy. Let us seek refuge in His Word for peace while we rest to rise refreshed and confident in the victory God has won. We will be fearless, for what have we to fear among those who do good? And if God is for us, who can be against us? Then we will look back on our trouble and smile, saying, “To God be the glory, great things He has done.” May He give you peace in your sorrow and joy in your pain in Christ Jesus, our Lord. Amen.