Because, in time, the better arguments sway reasonable people. A reader writes:
Yesterday I attended the funeral of Dr. Richard Garibaldi, the Chairman of the Department of Medicine at the University of Connecticut. The Catholic priest who was conducting the funeral mass heralded Dr. Garibaldi's moral courage and championing of society's underdogs. As an example, the priest talked about an incident a couple of years ago, when the priest had reluctantly–but out of obedience to ecclesiastical authority–read from the altar a pastoral letter whose subject was the "objectively disordered" nature of homosexuality.
After the mass, Dr. Garibaldi–a mensch in the true sense of the word–approached the priest and expressed profound disappointment in the letter. Dr. Garibaldi discussed how homosexuality is actually a normal and natural part of humanity, and he told his parish priest that the Church "shouldn't kick a group that doesn't deserve kicking."
Yesterday, while standing over Dr. Garibaldi's coffin and standing before Dr. Garibaldi's widow, family, and hundreds of their friends, this priest apologized for having read the letter. The priest said that he had been moved by Dr. Garibaldi's appeal. The priest apologized and said that he would never again read such a letter from the altar.