We learn about one early Catholic who met with a group of concerned Protestants at an early ecumenical meeting in Acts 7:51—8.
“Stephen said to the people, the elders, and the scribes: “You stiff-necked people, uncircumcised in heart and ears, you always oppose the Holy Spirit; you are just like your ancestors. Which of the prophets did your ancestors not persecute? They put to death those who foretold the coming of the righteous one, whose betrayers and murderers you have now become. You received the law as transmitted by angels, but you did not observe it.”
When the Protestants at that early ecumenical meeting heard this, they avoided listening to another point of view.
“When they heard this, they were infuriated, and they ground their teeth at him. But Stephen, filled with the Holy Spirit, looked up intently to heaven and saw the glory of God and Jesus standing at the right hand of God, and Stephen said, “Behold, I see the heavens opened and the Son of Man standing at the right hand of God.” But they cried out in a loud voice, covered their ears, and rushed upon him together.”
On hearing this astonishing news, the Protestants at this early ecumenical meeting did not stop to consider Stephen’s astonishing vision. They did not seem to be at all interested in what appeared before his very eyes. Instead of listening,
“They threw him out of the city, and began to stone him. The witnesses laid down their cloaks at the feet of a young man named Saul. As they were stoning Stephen, he called out, “Lord Jesus, receive my spirit.” Then he fell to his knees and cried out in a loud voice, “Lord, do not hold this sin against them”; and when he said this, he fell asleep.”
One of those Protestants at the early ecumenical meeting went on to become a Catholic priest. After his name was changed from Saul to Paul, he began providing The Body and Blood of Jesus Christ at the Catholic Masses held after The Last Supper. St. Paul explained in his First Letter to the Corinthians, 10:16, “This cup of benediction that we bless is it not a participation in The Blood of Christ. This bread that we break is it not a participation in The Body of Christ.”
So, one of the Protestants at an early ecumenical meeting that brought death to one Catholic brought life to millions more. We learn from St. Paul and the martyrdom of St. Stephen that “all things work together for good”.