What is the meaning of Acts 23:22-24?

22 So the chief captain then let the young man depart, and charged him, See thou tell no man that thou hast shewed these things to me. 23 And he called unto him two centurions, saying, Make ready two hundred soldiers to go to Caesarea, and horsemen threescore and ten, and spearmen two hundred, at the third hour of the night; 24 And provide them beasts, that they may set Paul on, and bring him safe unto Felix the governor. (Acts 23:22-24 KJV)

William Burkitt’s Commentary

Observe here, 1. How wonderfully God overruled the heart of the chief captain, in that he took care both of St. Paul and the young man also: he bids the young man depart; for had it been known that the boy had discovered the conspiracy, they had conspired against his life. And had not the chief captain conveyed away the apostle, his enemies, who had been disappointed in the first plan, would have made further attempts against his life. Thus wonderfully does the good providence of God work for his servants’ preservation.
Observe, 2. What a strong guard does God raise and set round apostle Paul for his defence and safety, that is a guard of heathen soldiers to secure him from the Jewish rage; two hundred soldiers, threescore and ten horsemen, and two hundred spearmen.
What a royal lifeguard was here raised for the apostle’s safe conduct to Cesarea! None of all these soldiers intended him any good, but God can make bad persons show kindness to his good servants, and do his will by them who know nothing of his mind and will.
When God has work to do, he will find instruments through whom he will do it. And though we do not see them, yet are they never the farther off.