Pope Benedict XVI pressed ahead with his appeals for a unified church Thursday as he a celebrated a Mass in St. Peter's Basilica attended by a delegation of Orthodox Christians."We again implore, on this occasion, that such a a gift be granted soon," Benedict said.Benedict has made uniting all Christians and healing the 1,000-year-old rift with the Orthodox a primal goal of his papacy, although he acknowledged key differences.He combined his call for Christian unity with a warning that the Catholic Church was threatened by those seeking to "push it outside the world.""Again the little boat of the church is...