Acts 28:21-25
Acts 28:21 (KJB)
And they said unto him, We neither received letters out of Judaea concerning thee, neither any of the brethren that came showed or spake any harm of thee.
The leaders then told Paul that they had received nothing by way of a letter concerning Paul nor did they receive any brethren from Jerusalem concerning him. The Jerusalem accusers probably thought that it would be better if they stay away from Rome because Roman law permitted false accusers to be punished and the Jerusalem crowd were false accusers, especially when they hired a golden mouthpiece, Tertullus, to try and cajole Festus.
Acts 28:22 (KJB)
But we desire to hear of thee what thou thinkest: for as concerning this sect, we know that every where it is spoken against.
The Roman Jews had desired to hear what Paul had to say about Christianity, which they deemed a sect, because they heard that this sect is spoken against everywhere. Up to this point, they only knew about it from a negative standpoint but now their desire to know more about it has been aroused and Paul gets another chance to tell the truth about the reality of Christianity and the fact that Jesus is the Messiah.
Acts 28:23 (KJB)
And when they had appointed him a day, there came many to him into his lodging; to whom he expounded and testified the kingdom of God, persuading them concerning Jesus, both out of the law of Moses, and out of the prophets, from morning till evening.
Since Paul was allowed to have guests, the Jews had now set a date when they would come to Paul and discuss the situation. When that day came, there were many who came to Paul and had desired to hear what he had to say. Then just as Paul did in all the synagogues that he visited, he began to explain to them about Jesus being the Messiah and he started with the books of Moses, known as the Torah, where he would explain from these five books how Jesus fulfilled the prophecies such as Deuteronomy 18. (Deu 18:15 KJV) The LORD thy God will raise up unto thee a Prophet from the midst of thee, of thy brethren, like unto me; unto him ye shall hearken; Then Paul not only taught from the Torah but from the prophets where he would find many prophecies of the coming of Messiah such as Micah 5:2. (Micah 5:2 KJV) But thou, Bethlehem Ephratah, though thou be little among the thousands of Judah, yet out of thee shall he come forth unto me that is to be ruler in Israel; whose goings forth have been from of old, from everlasting. The Pharisees would have acknowledged the prophets but not the Sadducees. Paul did not only speak in a cursory way but he expounded the Scriptures from morning till night. This is a great lesson for Christians. Whenever we need to reason something out about Christianity, it should be done from the Scriptures themselves and not incessant quotes by men.
Acts 28:24 (KJB)
And some believed the things which were spoken, and some believed not.
As was Paulís custom to reason with the Jews, it also yielded the same fruit as in the past. Some were convinced about the reality of Jesus being the Messiah and the verity of Christianity but some did not believe. Nevertheless, Paul was able to make his case and to give them a further understanding of Christianity from the Scriptures. They now understood a little more and not only from the negative point of view bit from the biblical point of view.
Acts 28:25 (KJB)
And when they agreed not among themselves, they departed, after that Paul had spoken one word, Well spake the Holy Ghost by Esaias the prophet unto our fathers,
The fact that some believed and some did not caused a disagreement and a line of separation between them. Jesus had already warned that the truth of the Gospel was going to bring division. (Luke 12:51 KJV) Suppose ye that I am come to give peace on earth? I tell you, Nay; but rather division: Paul then begins to quote Isaiah because he identifies with the ministry of Isaiah in dealing with the nation of Israel, their ministries were very similar in nature.