Archbishop Orani João Tempesta of Rio formally opened World Youth Day 2013 at a Mass on Copacabana Beach last night (full text, photos, short video, full video). Rwandan authorities have arrested 11 members of a breakaway Catholic group after they attempted to deliver an alleged message from the Virgin Mary to president Paul Kagame. Cardinal Luis Antonio Tagle of Manila has opened an official Twitter account. Tom Gallagher says Mgr Leo Cushley, Archbishop-elect of St Andrews and Edinburgh, has the daunting task of breathing new life into the Scottish Church. Justin Bell describes what he discovered on a tour of a Rio slum this week. Laurence England urges bishops to speak out about the scourge of internet pornography. And Joan Frawley Desmond calls for a zero-tolerance crackdown on revealing clothing at Mass. Follow me on Twitter @lukecoppen for updates throughout the day. The next Morning Catholic must-reads will be on Friday, July 26