Thanks for your question about the verses in Psalm 37!
If we look at the entire psalm, we can see that God is encouraging us to look long term.
For example, verses 28 to 29 says:
"For the Lord loves justice
And does not forsake His godly ones;
They are preserved forever,
But the descendants of the wicked will be cut off.
The righteous will inherit the land
And dwell in it forever." (Psalm 37:28-29)
Even though believers are persecuted and even die for their faith, what they experience is only temporary pain and momentary affliction. In fact, the Bible often says that believers "fall asleep" when they die (1 Thessalonians 4:13-14). What does falling asleep mean but that they will awaken again.
When we look at suffering in the context of a few years compared to the weight of eternity, our suffering is not lasting and is not something we should focus on.
The apostle Paul wrote: "For momentary, light affliction is producing for us an eternal weight of glory far beyond all comparison, while we look not at the things which are seen, but at the things which are not seen; for the things which are seen are temporal, but the things which are not seen are eternal." (2 Corinthians 4:17-18)
Even Jesus talked about persecutions and how many will die for the faith. But He also said that none of their hair will even be missing!
"But you will be betrayed even by parents and brothers and relatives and friends, and they will put some of you to death, and you will be hated by all because of My name. Yet not a hair of your head will perish. By your endurance you will gain your lives." (Luke 21:16-19)
So how is it possible that people are persecuted and even put to death but not a hair will perish? It is possible because God preserves those who follow Him. If we don't give up on following God, we will be rewarded and live forever.
"The wicked spies upon the righteous
And seeks to kill him.
The Lord will not leave him in his hand
Or let him be condemned when he is judged.
Wait for the Lord and keep His way,
And He will exalt you to inherit the land;
When the wicked are cut off, you will see it." (Psalm 37:32-34)
These verses tell us that even though the enemies of God seek to kill God's people, we will not be given over to them forever. Nor will we be condemned before God when we are judged. We should wait for the Lord and keep His way.
At the resurrection of the saints, God will exalt us to inherit heaven and earth. When God brings righteousness on earth and condemns the wicked, we will see it.
I pray this will encourage you. And help you not focus on short term afflictions but see more clearly the things of eternity.