What does Acts 11:15 mean?

Peter returned from an amazing experience in Caesarea Maritima to Jerusalem just to be accused of eating with uncircumcised Gentiles (Acts 11:2–3). The charges are true, but the circumstances are extraordinary. And the act, itself, is not a sin in any sense. Peter explains how he was praying on a rooftop in Joppa when he received a vision wherein God told him the Mosaic laws against eating certain foods has been nullified. Immediately after the vision ended, three strangers invited Peter to visit with a Roman centurion, Cornelius, in Caesarea. Peter and six Jewish Jesus-followers from Joppa went to Cornelius and found a houseful of Gentiles ready to hear the story of Jesus (Acts 10:1–33).

Peter explained to Cornelius' guests that God sent Jesus to the Jews, but he realizes Jesus is for anyone of any nation willing to accept him. He also told of how Jesus was baptized by John the Baptist and ministered throughout Judea and Galilee before being crucified. Cornelius and his guests knew this much (Acts 10:34–39).

As a soldier, Cornelius would have heard the rumors about the empty tomb. The soldiers tasked with securing the stone over the doorway (Matthew 27:62–66) lost all executive function when the angels arrived (Matthew 28:4). The priests bribed them to say the disciples stole Jesus' body (Matthew 28:11–15). There's no telling what part of this Cornelius was familiar with, but Peter explained that Jesus rose from the dead and then He met with some of His followers and told them to teach others about Him (Acts 10:40–43).

At this point, the Holy Spirit came down on Cornelius, his friends, and his family. He came down without Peter laying his hands on them and gave them the ability to speak other languages, as He had for the Jesus-followers "at the beginning" on Pentecost (Acts 2:4; 10:44–46). Yes, Peter ate with uncircumcised Gentiles, but these were full-fledged members of the church.