The Church can persuade people to the extent that its messengers are willing to be vulnerable.

“I have fought the good fight,” says Paul to his dearest student Timothy face to face with death, as he reflects on the path of his life. Such words imply that Paul liked to be labeled a fighter, a man of action, indeed, a combative nature. … (The fight of Saint Paul was not the fight of some careerist, a man of power, and certainly not that of a ruler or conqueror. It was a fight, as Teresa of Avila describes it: her words “God wants and loves courageous souls” are explained by the following sentence: “The first thing the Lord does with His friends when they grow weak is that He gives them courage and takes away the fear of suffering.”)

It was precisely his willingness to risk everything, his selflessness, his exposure to wounds, and his consumption for the gospel that made him credible. From his letters, we know that he was everything but a great orator. “When he is here, he is a weakling, and his speech is worth nothing” (2 Cor 10:10), his opponents said about him. Paul did not operate through brilliant rhetoric and refined strategies, but by investing and giving himself for his message. Even today, the church can convince people to the extent that the proclaimers are willing to be wounded. Where there is a lack of willingness to suffer, there is a lack of the decisive test of truth to which the church is bound. Its struggle can only ever be the struggle of those who are willing to give themselves – it is the struggle of martyrs.

(Cardinal Joseph Ratzinger, meditation on the feast of the Conversion of Saint Apostle Paul)