Why was it unlawful for Peter to go into Cornelius's house?
It was unlawful under the law for a Jew to keep company with or come unto one of another nation. Peter, a law keeper, recognized this restriction, so entering Cornelius's house violated that separation. God later showed him not to call any man common or unclean.
Les explains that Peter was coming back to the law when he called it unlawful. The law forbade a Jew to keep company with or come unto one of another nation. The Romans in Palestine understood the Jewish community, so Peter acknowledged this restriction to Cornelius. But Peter added that God had shown him he should not call any man common or unclean. Les points out that God showed him this in the vision of the sheet with clean and unclean animals, and Peter realized it was not merely about eating food but about the human race. The apostle of the Gentiles had been saved in chapter 9, and the gates were now opening to Gentiles; chapter 11 would widen it, and in chapter 13 Paul and Barnabas went out on missionary journeys largely to Gentiles while Jews rejected it. Peter, a law keeper who had never eaten anything common or unclean, was uncomfortable entering Cornelius's house because it was unlawful for a Jew to go into a Gentile's house.
And he said unto them, Ye know how that it is an unlawful thing for a man that is a Jew to keep company, or come unto one of another nation; but God hath shewed me that I should not call any man common or unclean.
More Questions
Was the law still in effect by the time Peter went to Cornelius's house?
By the time of Acts 10, the law had not been set aside, so the idea that as soon as you get into Matthew you are in the Christian economy is mistaken.
Why did Peter say it was unlawful for a Jew to associate with Gentiles?
In Acts 10:28 Peter calls it 'unlawful' for a Jew to keep company with or go into the home of a Gentile.
What did Peter say to Cornelius when he arrived at his house?
When Peter entered Cornelius's house, he told Cornelius that it was unlawful for a Jew to come into the house of another nation.
Was it unlawful for a Jew to associate with a Gentile in Acts 10:28?
Peter said it was an unlawful thing for a Jew to keep company with or come to a Gentile, as he explained to Cornelius's household.