Peter didn't preach "God's love and acceptance of the nations." He witnessed to ONE Cornelius, a Gentile God-Fearer, and one not circumcised but still one step away from the Abrahamic Covenant. Peter was apostle to the Jews, not the "all nations."
Peter Preaches to the Gentiles – Acts 10:1-11:30
Cornelius
1Now there was a man at Caesarea named Cornelius, a centurion of what was called the Italian cohort, 2a devout man and one who feared God with all his household, and gave many alms to the Jewish people and prayed to God continually. 3About the ninth hour of the day he clearly saw in a vision an angel of God who had just come in and said to him, "Cornelius!" 4And fixing his gaze on him and being much alarmed, he said, "What is it, Lord?" And he said to him, "Your prayers and alms have ascended as a memorial before God. 5Now dispatch some men to Joppa and send for a man named Simon, who is also called Peter; 6he is staying with a tanner named Simon, whose house is by the sea." 7When the angel who was speaking to him had left, he summoned two of his servants and a devout soldier of those who were his personal attendants, 8and after he had explained everything to them, he sent them to Joppa.
- Acts 10:1-8
The Jews had two classes of converts (Lenski, p.67):
Proselytes of the Gate: These converts were not subject to circumcision and observed only a limited portion of the Law forbidding idolatry, blasphemy, disobedience to judges, murder, fornication/incest, theft and eating of blood. The eunuch that Philip baptized was one of these as was Cornelius, probably because he was a Roman soldier and a foreigner.
Proselyte of Righteousness: These were Gentiles that became complete Jews, accepting circumcision, and were subject to all of the Law. They were permitted to enter and worship at the Temple (in the Court of the Gentiles).
Although he was a Proselyte of the Gate, Luke describes Cornelius (centurion is a Roman officer over 100 soldiers) as being:
Devout/pious: A proselyte who worshiped the God of the Jews and led his household in that direction.
Benevolent: He used his position and wealth to benefit the poor thus confirming that his faith was sincere.
Spiritually minded: He wanted a spiritual relationship with God and pursued it through prayer.
His prayers are answered as God gives him instructions to bring Peter to his home. Note that the angel could have preached the gospel to him then and there, but that task was given by God to men not angels, so that even if it was more complicated to arrange, Cornelius sends for Peter.
Peter
9On the next day, as they were on their way and approaching the city, Peter went up on the housetop about the sixth hour to pray. 10But he became hungry and was desiring to eat; but while they were making preparations, he fell into a trance; 11and he saw the sky opened up, and an object like a great sheet coming down, lowered by four corners to the ground, 12and there were in it all kinds of four-footed animals and crawling creatures of the earth and birds of the air. 13A voice came to him, "Get up, Peter, kill and eat!" 14But Peter said, "By no means, Lord, for I have never eaten anything unholy and unclean." 15Again a voice came to him a second time, "What God has cleansed, no longer consider unholy." 16This happened three times, and immediately the object was taken up into the sky.
- Acts 10:9-16
God provides a vision where Peter is commanded to eat food that Jews were not permitted to eat according to Jewish food laws. The Lord had prepared Cornelius for Peter's visit with the appearance of an angel who gave him specific instructions. God also prepares Peter so that he will be able to carry out God's mission despite the challenges it will present him as a faithful Jew.
Jewish ceremonial and food laws were given to the Jews by God in order to make a distinction between themselves as God's people and other nations (Gentiles) who were not. For example, the whole world labored seven days per week, but the Jews were different in that they devoted one day (Sabbath) to the Lord and rested. The other nations ate every kind of food. Jews were different because what they did or did not eat was guided by their law given to them by God. Once Christ came, the way to be separated from the world was to follow Him and submit to the direction of the Holy Spirit who leads Christians through His Word (New Testament) spoken by Christ and taught by His Apostles (Acts 2:42).
The problem for Peter as well as the other Apostles was that the practices that they had followed as Jews (food laws, Sabbath day observations, etc.) were now taken away or fulfilled by Jesus, but they were slow to understand. This included the rules concerning their association with Gentiles. For example, they could not enter a Gentile's home or share a meal with them, nor could the Gentiles enter a Jew's home or the Temple.
In the vision of the clean and unclean food and the command to eat, God was teaching Peter two things:
God had the authority to establish laws, change laws, or suspend laws because He was God, the giver of laws.
He was now amending the law concerning food, declaring that all food was to be considered "clean" and thus could be eaten freely by Jewish Christians (something Jesus had already declared in Mark 7:19).
17Now while Peter was greatly perplexed in mind as to what the vision which he had seen might be, behold, the men who had been sent by Cornelius, having asked directions for Simon's house, appeared at the gate; 18and calling out, they were asking whether Simon, who was also called Peter, was staying there. 19While Peter was reflecting on the vision, the Spirit said to him, "Behold, three men are looking for you. 20But get up, go downstairs and accompany them without misgivings, for I have sent them Myself." 21Peter went down to the men and said, "Behold, I am the one you are looking for; what is the reason for which you have come?" 22They said, "Cornelius, a centurion, a righteous and God-fearing man well spoken of by the entire nation of the Jews, was divinely directed by a holy angel to send for you to come to his house and hear a message from you." 23So he invited them in and gave them lodging.
- Acts 10:17-23a
Peter, still trying to absorb the meaning of the vision, is told that the men sent by Cornelius are at the gate and he should welcome them. Peter greets them and after hearing the reason for their journey invites them to spend the night with him and Simon's family. Peter may not have understood the full impact of the vision but nevertheless obeyed God's instructions to invite the Gentiles in, despite his discomfort.
Peter Meets Cornelius
23bAnd on the next day he got up and went away with them, and some of the brethren from Joppa accompanied him. 24On the following day he entered Caesarea. Now Cornelius was waiting for them and had called together his relatives and close friends. 25When Peter entered, Cornelius met him, and fell at his feet and worshiped him. 26But Peter raised him up, saying, "Stand up; I too am just a man." 27As he talked with him, he entered and found many people assembled. 28And he said to them, "You yourselves know how unlawful it is for a man who is a Jew to associate with a foreigner or to visit him; and yet God has shown me that I should not call any man unholy or unclean. 29That is why I came without even raising any objection when I was sent for. So I ask for what reason you have sent for me."
30Cornelius said, "Four days ago to this hour, I was praying in my house during the ninth hour; and behold, a man stood before me in shining garments, 31and he said, 'Cornelius, your prayer has been heard and your alms have been remembered before God. 32Therefore send to Joppa and invite Simon, who is also called Peter, to come to you; he is staying at the house of Simon the tanner by the sea.' 33So I sent for you immediately, and you have been kind enough to come. Now then, we are all here present before God to hear all that you have been commanded by the Lord."
- Acts 10:23b-33
Luke describes both Cornelius' preparations for Peter's visit (he had no doubt that the Apostle would come). There is also a marvelous image of these two pious and humble men deferring to one another. Cornelius, a Roman Centurion, kneeling in front of this Galilean fisherman in front of his family and friends. And the servant of the Lord refusing this type of homage declaring the truth that before God both of them were only men (sinful men).
Peter begins by speaking to the obvious issue, "What are a group of Jewish men doing visiting/entering the house of a Gentile?," something that everyone knew was not permitted for a Jew. He does not describe his vision, as Cornelius will do in a moment, but demonstrates that he has understood the meaning of the vision God gave him and that he has obeyed it. Cornelius explains his own vision and how this has led to Peter's arrival in his home
. The stage has now been set for the first instance where the gospel will be proclaimed to the Gentiles.
Peter Preaches to the Gentiles (10:34-43)
Peter's lesson assumes that his hearers are all familiar with the facts of the gospel as were most of the people who lived in that area and knew of Jesus, His ministry, as well as His death and reports of His resurrection. He also includes the new information given him by God in the vision that the gospel is for all, not only the Jews to whom he had been preaching since Pentecost. His main point is that he and the Apostles are actual witnesses of the death, burial and resurrection of Jesus.
39We are witnesses of all the things He did both in the land of the Jews and in Jerusalem. They also put Him to death by hanging Him on a cross. 40God raised Him up on the third day and granted that He become visible, 41not to all the people, but to witnesses who were chosen beforehand by God, that is, to us who ate and drank with Him after He arose from the dead. 42And He ordered us to preach to the people, and solemnly to testify that this is the One who has been appointed by God as Judge of the living and the dead. 43Of Him all the prophets bear witness that through His name everyone who believes in Him receives forgiveness of sins."
- Acts 10:39-43
Response to Peter's Preaching (10:44-48)
44While Peter was still speaking these words, the Holy Spirit fell upon all those who were listening to the message. 45All the circumcised believers who came with Peter were amazed, because the gift of the Holy Spirit had been poured out on the Gentiles also. 46For they were hearing them speaking with tongues and exalting God. Then Peter answered,
- Acts 10:44-46
Before Peter can finish by encouraging his audience to repent and be baptized as he did with the crowd on Pentecost Sunday, Cornelius and the other hearers begin speaking in tongues and praising God. Luke describes this phenomenon as, "the gift of the Holy Spirit poured out on the Gentiles."
Think back to other times in the book of Acts when the Holy Spirit was mentioned and answer this question, "What has just happened here: empowerment by the Holy Spirit or indwelling of the Holy Spirit?" The answer is: empowerment. The Holy Spirit empowered these people to speak in tongues. I believe this happened in order to convince those that did not have a vision (like Peter's companions) that God was extending the gospel to the Gentiles, not only to the Jews. There were many prophets who said that this would be so (Micah 4:2; Zechariah 8:22; Amos 9:12) including Jesus Himself in Mark 13:10.
47"Surely no one can refuse the water for these to be baptized who have received the Holy Spirit just as we did, can he?" 48And he ordered them to be baptized in the name of Jesus Christ. Then they asked him to stay on for a few days.
- Acts 10:47-48
Peter now finishes his lesson by directing these new believers to be baptized because if there were any who doubted that the gospel was also for the Gentiles, their questions had been answered by the Holy Spirit Himself when He empowered these people to speak in tongues. Peter mentions that they had received the empowerment by the Holy Spirit just like the Apostles did, without human intervention (no laying on of hands). He also insists that they be baptized in order to obey the gospel and receive the indwelling of the Holy Spirit (Acts 2:38).
And so God uses the appearance of an angel, a special vision and the empowering of Gentiles to direct Peter to open the gospel to non-Jews. We find out that all of this and more would be necessary to convince the early church, made up exclusively of Jewish Christians, to accept this directive from God.