The unknown author of this psalm begins with a strong assertion of the reality of answered prayer (v. 1). He is experiencing difficulties which make him very distressed. Yet he provides us with the key of how to endure them, and the key is fresh, ongoing prayer. We know that it is easy to focus on problems to such an extent that we forget to pray while they are happening. But the psalmist assures us that we can maintain a regular prayer contact with God in such times.
The psalmist also makes clear that times of difficulty are also periods of receiving answers to prayer. No doubt the divine answers were connected to various kinds of help that the psalmist needed. Perhaps he was afraid of what would happen to him, so he needed assurance that God would help him. Perhaps he was lonely and needed a sense of divine companionship. Whatever it was that he requested, the Lord answered the prayer in a manner that helped the psalmist.
One of the concerns that the psalmist had, and the one that he mentions specifically, was the unreliability of the words of those he came in contact with (verse 2). It looks as if they were either lying to or lying about the psalmist. One of the most difficult experiences that Christians have is to deal with those who do not tell the truth to them or about them. It is not surprising that the psalmist turned to speak to the One who is the truth.
In verses 3 and 4, the psalmist speaks to or about those with false tongues. He asks the all-important question, which is, What will God do to those who tell lies? The answer is that he will come against such as a warrior. Perhaps the illustration of an archer with fiery arrows suggests that he will fire back into them the untruths they have spoken, but these untruths will now cause them great distress and fear. We can imagine what it is like to be found a liar in a court case. How much sorer will it be to be found a liar in God's courtroom!
Or it could be that the psalmist is indicating that the divine response will involve some form of battle as a divine punishment. The liars here may have been plotting against David (if he was the unknown author) and he realised that his rebellious opponents would be punished by his soldiers. If this was the scenario, it is a reminder that God sometimes uses the civil authorities as instruments of his punishment.
The psalmist likens his current experience to living far from where he wanted to be (verses 5-7). Meshech is in modern Turkey and Kedar is probably in modern Arabia. Obviously be could not be in both places at once. He is using those far-off geographical locations to illustrate that he is far from a place of peace. Christians dislike places where there is no peace, which is why unnecessary church disputes are so disturbing to them.
The phrase 'I am for peace' is a good motto for Christians and a good mission statement for a church. We can apply this phrase in all kinds of ways. In addition to personal peace with God and peace with one another, they have a message of peace for the world.