Yes, prayer changes things. There are many reasons for prayer and we are told to pray unceasingly (1 Thess 5:17).
John MacArthur notes:
The early church was marked by this kind of continual, passionate, unceasing prayer from the very start. Even before the day of Pentecost in Acts 1:14, all the believers were one, it says; one mind, and continually devoting themselves to prayer. Incessant prayer, constant prayer, persistent prayer marked the early church. When the apostles were structuring the church so that all the ministry could be accomplished, they themselves said, “We can’t do all of these routine things, but we will devote ourselves to prayer. We will devote ourselves to prayer and the ministry of the Word.”
So what should we be praying for and how should we pray? We can pray for our genuine needs, and for the salvation and needs of others. Most importantly, our prayers should be aligned with God’s will.
We also believe that Christians are living at a critical juncture in this world’s history. Our world is becoming increasingly hostile to the faithful Christian. Where Christians aren’t being persecuted or slaughtered, there are mounting pressures to accommodate a godless society. There are even pressures working in many churches to abandon the biblical inerrancy and Christ’s exclusivity in favor of religious pluralism. All these issues (and more) call for us to pray fervently, incessantly and in the Spirit.
What does it mean to pray in the Spirit? It might not mean what many may take it to be. William Gurnall has responded to this question in detail in his classic The Christian in Complete Armor. You can read an extract on the subject of praying in the Spirit HERE
Dr. Paul Henebury writes on the relationship between prayer and watchfulness in context to the Armor of God:
Now, prayer is finally mentioned (v. 18). Some include it as part of the Christian armor, but we think that the apostle is likening it to watchfulness. A man can be watchful, whether he is armed or not. Prayer keeps us spiritually alert. By continual communion with God, and by making requests of Him (i.e. supplication) we can maintain an awareness of the needs of both ourselves and of others. We are to look out prayerfully for all saints. Paul even includes himself in this number.
On this matter of prayer, we cannot pass over the exhortation of one greater than ourselves. “Let us stir up ourselves to keep this watch that we may see, and walk in the strength of our prayers…If we should devise anything by way of petition [e.g. to a magistrate] should we not wait [to see] how it is received? what is said to it? Would we give our petition, and carelessly depart, never thinking on it? How much more should we wait and see what will become of our requests to God?” (Paul Bayne, 670)
In his situation, in a prison in Rome, Paul covets the prayers of the Ephesian church. He asks them to pray that when he comes before Caesar, he may speak boldly as an ambassador of Christ (2 Cor. 5:20) though in bonds (v. 20). In a way not explained in Scripture, God has allowed Himself to be moved by our prayers. Some Christians tell us that prayer doesn’t change things it simply aligns us with the will of God. But that hardly fits the petition that Paul is making here. Surely, a great incentive to pray is that prayer can change things. How? The same way obedience works. God knows we will produce fruit before we obey, but the fruit produced is contingent upon that obedience. Likewise, if we don’t pray, we cannot expect the answer that God would have decreed on the basis of it. (Underlining ours)
Dr. Henebury’s full treatise on Ephesians 6:10-20 can be read HERE
We also highly recommend reading the rest of his observations on Ephesians HERE
Sadly, prayer has been largely abandoned or neglected by many modern professing Christians. Now is an urgent time to revive it. We may not be able to change the world – God has ordained what will be – but, as in the Apostle Paul’s situation, God still works through the Christian’s prayer to bring about His will.
That’s a very comforting and sobering thought.