Paul in Rome

Who established the church in Rome?
God used someone other than Paul, since this was Paul's first visit to Rome. But Paul and the church in Rome weren't strangers. Before heading to Jerusalem, most probably from Corinth - "But now I am going to Jerusalem to minister to the saints. For it pleased those from Macedonia and Achaia to make a certain contribution for the poor among the saints who are in Jerusalem" (Romans 15:25-26) - Paul wrote to the church in Rome and shared his prayers, now granted: "To all who are in Rome, beloved of God, called to be saints: Grace to you and peace from God our Father and the Lord Jesus Christ. First, I thank my God through Jesus Christ for you all, that your faith is spoken of throughout the whole world. For God is my witness, whom I serve with my spirit in the Gospel of His Son, that without ceasing I make mention of you always in my prayers, making request if, by some means, now at last I may find a way in the will of God to come to you. For I long to see you, that I may impart to you some spiritual gift, so that you may be established - that is, that I may be encouraged together with you by the mutual faith both of you and me" (Romans 1:7-12).

How many Christians did the Roman Christians greet?
Since the "centurion" (Acts 28:16) was with Paul, so were his soldiers and the other prisoners bound for Rome, as well as perhaps the other passengers from the ship who were bound for Rome. After what they had witnessed, lived through and heard from Paul since leaving Caesarea, it is highly likely that the Roman Christians greeted many more Christians than just Paul, Luke and Aristarchus, as many of the passengers who had been on the ship that wrecked in Malta may have been saved in more ways than one.

To whom did the centurion deliver the prisoners upon arrival in Rome?
The head of the Praetorian guards - "captain of the guard" (Acts 28:16) - who guarded Caesar and his palace.

Why was Paul "permitted to live by himself with the soldier who guarded him" (Acts 28:16)?
For one, he was an uncondemned Roman citizen. For another, the centurion may have vouched for Paul.

Why then did the Lord have "soldiers" guard Paul?
To protect him during his ministry in Rome: "Then Paul lived two whole years in his own rented house, and received all who came to him, preaching the kingdom of God and teaching the things which concern the Lord Jesus Christ with all confidence, no one forbidding him" (Acts 28:30-31).

What happened to the soldier guarding Paul?
God turned them into Christians, as Paul later wrote to the church in Philippi: (the original Greek word translated "household" is οικιας (oikias), which can mean either "household" or "house," which for the Caesar is his palace): "Greet every saint in Christ Jesus. The brethren who are with me greet you. All the saints greet you, but especially those who are of Caesar’s household." (Philippians 4:21-22)

What did Paul's guard do in turn?
Spread the Gospel to the "whole" Praetorian guards, as Paul also wrote: "But I want you to know, brethren, that the things which happened to me have actually turned out for the furtherance of the Gospel, so that it has become evident to the whole palace guard, and to all the rest, that my chains are in Christ" (Philippians 1:12-13).