There is a type of Psalm that many have categorized as "Royals Psalms," because they deal with the king. There are ten Psalms that come under this category, which include 2, 18, 20, 21, 45, 72, 89, 110, 132, and 144. These Royal Psalms are sometimes prayers for the king, of the king, or concerning the king. Some of them apparently serve as coronation Psalms for the kings.
The 2nd Psalm, which along with the 1st Psalm serves as an introduction to the Psalter, is a Royal Psalm that attests to Yahweh's backing of his anointed king. This makes Yahweh's anointed one invincible, as we see in 1 Sam 17 where young David defeats Goliath after being anointed in chapter 16. No wonder the Psalm ends with a beatitude, "O the blessedness of all who take refuge in him!"
However, the kings of Israel and the people did not always take refuge in Yahweh, but in making treaties with pagan nations and seeking out pagan gods. They obviously did not take Psalms such as this one very seriously. As a result of their lack of trust and loyalty to God, they fell to the nations.
But God was not through. Without the existence of the physical monarchy, many of the Royal Psalms were read as Messianic Psalms. Read this way, they looked forward to a future hope where God would once again enthrone his anointed.
And then he came into the world. The anointed one. The Messiah. The King. They killed him, but all that did was free his subjects from sin. They buried him. But he rose from the grave and freed everyone from bondage to death. He ascended and sent the Holy Spirit to strengthen his followers. They tried to stop his followers, but it was a futile effort. They kept multiplying. They were everywhere!
On one occasion, after a persecution, his followers prayed part of Psalm 2 in Acts 4:25f. The authorities tried to stop the Lord's anointed, but couldn't Why did they devise futile things? Did they not know that they could not stop him or his followers? They could drag off, intimidate, persecute, and kill these Christians, but it was all futile. As the Psalm says, "He who sits in the heavens laughs.." There is nothing they can do to stop it.
What a powerful reminder. These Royal Psalms can still be a powerful prayer and reminder for us that we are on God's side and his anointed one, Jesus Christ. Therefore any effort against us is futile. They cannot touch us. If they intimidate us, we will still press forward. If they persecute us, we will get stronger. If they kill us, we go to be with the Lord and others will take our place.
There is no reason to fear anyone or anything. There is no reason to be timid. There is every reason to be bold and confident in the face of any resistance to our faith. If God is for us, who can be against us? No one!
Christians (that's us) have marched forward with the saving Gospel since the beginning and will continue to do so because we are on God's side!