Pope Francis celebrated Sunday Mass Service at the Church of Sant'Anna at the Vatican, prior to delivering his first Angelus prayer. He then delivered his Angelus prayer and blessing to the pilgrims gathered in St Peter’s Square. The new pope also issued his first tweet shortly after performing his first Angelus prayer, with a consistent message: "Pray for me." "Dear friends, I thank you from my heart and ask you to continue to pray for me," the Argentine pope tweeted from the @Pontifex account. The inauguration mass of Pope Francis will be held on March 19, 2013 in Vatican City.