When God wanted to convince Peter that the law is no longer applicable, that the barrier between Jews and Gentiles was now broken down, He commanded Peter to do something against the law. Peter disobeyed and yet was not condemned. Grace in illustration.
Luke wrote of this encounter of Peter,
“About noon the following day as they were on their journey and approaching the city, Peter went up on the roof to pray. 10He became hungry and wanted something to eat, and while the meal was being prepared, he fell into a trance. He saw heaven opened and something like a large sheet being let down to earth by its four corners. It contained all kinds of four-footed animals, as well as reptiles and birds. Then a voice told him, “Get up, Peter. Kill and eat.”
“Surely not, Lord!” Peter replied. “I have never eaten anything impure or unclean.”
The voice spoke to him a second time, “Do not call anything impure that God has made clean.” This happened three times, and immediately the sheet was taken back to heaven.” (Acts 10:9-16)
Do not call anything impure that God has made clean.