It is important to note that Cornelius' vision and Peter's vision along with their interaction is repeated in Acts several times. In chapter 10, Cornelius' vision with the angel is first recorded, still in chapter 10 Cornelius told some men close to him "what happened." Later, Cornelius' men told the story to Peter. Eventually, Cornelius told the story directly to Peter. Finally, Cornelius' story is repeated to the apostles in Judea by Peter. Having these visions repeated over and over in a single chapter tells us this is a very important and pivotal time and we need to pay attention to the message.
Cornelius was a Roman captain in the Italian Regiment. He was a God fearing man, devout and generous to the poor and respected by all the Jews. In fact, his entire household were God fearing. He was personally responsible for 100 soldiers. The regiment he was in was made up of 600 soldiers. He lived in Caesarea which was originally a Phoenician sea port on the Mediterranean Sea that had been taken over by the Romans. Caesarea was the primary location of the Roman government in Palestine and remained so for over 600 years. Caesarea was the location of a horrible conflict between the Romans and the Jews. In 66 A.D. the Romans in Caesarea executed 20,000 Jews in one day which was recorded by the Jewish historian Josephus. The killing of those Jews began the Jewish-Roman conflict eventually leading to the destruction of the Jewish Temple.
Cornelius was praying at his normal prayer time, about 3:00 in the afternoon, when he had a vision. An angel came to him and called to him. The angel told him his prayers and gifts to the poor had been received by God as an offering. The angel directed him to send men to Joppa and find a man named Peter who was staying with a man named Simon the tanner who lived by the seashore. He were to summon Peter to come to him.
Joppa (or sometimes Jaffa) was 35 miles south of Caesarea. Joppa means beauty in Hebrew. Like Caesarea, Joppa was also a Mediterranean sea port. Joppa is a suburb of today's city of Tel Aviv. We read in chapter 9 that Peter had gone to Joppa in response to men asking him to go there regarding the death of Tabitha. Peter went, prayed, and told her to get up and she did. Peter stayed in Joppa following that miracle.
The next day, Cornelius had the vision and sent his men to Joppa. About noon, the men sent by Cornelius were getting close to Joppa. At that time, Peter was on the flat roof of Simon's home, praying. As Peter prayed he was getting hungry. As a meal was being prepared, Peter fell into something like a trance. He saw the sky open and something like a large sheet was let down by it's four corners. The sheet was filled with all sorts of animals, reptiles and birds. (In a later telling of the vision, Peter said, "tame and wild animals.") Then a voice called to Peter and said, "Get up, Peter; kill and eat them. Peter said, "No Lord. I have never eaten anything that our Jewish laws have declared impure and unclean." The voice again spoke to Peter saying, "Do not call something unclean if God made it clean." That vision was repeated three times then the sheet was pulled back up to heaven.
Peter was perplexed and wondered what the vision meant. At that moment the men Cornelius sent to find Peter arrived at Simon's house asking if a man named Peter lived there. While they were asking for him, Peter was trying to understand what the vision meant. At that moment, the Holy Spirit said to Peter, "Three men have come looking for you. Get up, go downstairs, and go with them without hesitation. Don't worry, for I have sent them."
Peter got up, went downstairs and spoke to the men saying, "I'm the man you are looking for. Why have you come?" The men then told Peter the entire story of Cornelius and the angel's instruction to summon Peter to Cornelius so that he could hear his message. Peter invited them to spend the night and in the morning they left for Caesarea along with some of the brothers from Joppa.
They arrived in Caesarea the following day to find Cornelius waiting for them. Cornelius had invited and gathered his relatives and close friends to hear what Peter had to say. I can imagine he must have been very excited to hear from the man he was told by the angel to have come to his house. If an angel told any one of us a similar thing, I can only imagine being anxious and excited to hear him speak. It also had to be clear to both of them their meeting was arranged by God and therefore, must be very important.
When Cornelius saw Peter, he fell at his feet and worshipped him. Peter told him to stand up, explaining he was a human just like him. Peter and Cornelius talked for a while then went inside where the others were gathered to hear Peter speak.
Peter then seemed to understand the vision and said, "You know it is against our laws for a Jewish man to enter a Gentile home like this or to associate with you. But God has shown me that I should no longer think of anyone as impure or unclean. So I came without objection as I was sent for. Now tell me why you sent for me."
The gathering began with Cornelius telling Peter and his guests the complete story of his vision with the angel. He began with, "Four days ago I was praying in my house about this same time, three o'clock in the afternoon." He went on to tell of the angels and the instruction to send men to bring Peter back with them. Again the story was told in detail. Cornelius ended his story by saying, "So I sent for you at once and it was good of you to come. Now we are all here, waiting before God to hear the message the Lord has given you."
Peter replied, "I see very clearly that God shows no favoritism. In every nation He accepts those who fear Him and do what is right. This is the Good News for the people of Israel - that there is peace with God through Jesus Christ, who is Lord of all." This was the message he was to bring to those who were not Jews. This was God's plan that would be put into action by bringing Peter and Cornelius together. Peter spoke of the events in Judea beginning in Galilee. After John began preaching his message of baptism that God anointed Jesus of Nazareth with the Holy Spirit and with power. He talked about how Jesus then went around doing good and healing all who were oppressed by the devil. He could do those things because God was with Him.
Peter talked of the fact they were witnesses of all the things Jesus did throughout Judea and in Jerusalem. It was more than a story they had heard for they had actually been there. Peter spoke of them witnessing Jesus dong great things and even witnessed Him being put to death on a cross but that God raised Him from the dead on the third day. After Jesus had risen from the dead, God allowed Him to appear, not to the general public but to them and others God chose in advance to be His witnesses. Peter explained the had eaten with Jesus and drank with Him after He had risen from the dead. Jesus then ordered Peter and the others to preach everywhere and testify that Jesus is the One appointed by God to be judge of all the living and the dead. Peter went on to say, "He is the One all the prophets testified about, saying that everyone who believes in Him will have their sins forgiven through His name."
While Peter was speaking to them, the Holy Spirit fell upon all those who were gathered listening to the message. The Jewish believers who accompanied Peter were amazed that the gift of the Holy Spirit had now been given to the Gentiles too. They knew that for a fact for the Gentiles began speaking on other languages/tongues just as it had happened to them. They then heard them praising God.
Peter again spoke saying, "Can anyone object to them being baptized now that they have received the Holy Spirit just as we did?" Apparently, there were no objections because Peter then gave directions for those people to be baptized in the name of Jesus Christ. God set this entire plan into play. By doing so, the lives and message of the Jewish believers as well as the lives of the Gentiles, now believers, would be forever changed.
Following their baptism, Cornelius invited Peter and his men to stay with him and his other guests for several days.