At the 67-year-old singer's annual Aids benefit concert in New York City, the singer said Francis was pushing boundaries in the church, reported the Guardian.
"Ten years ago one of the biggest obstacles in the fight against Aids was the Catholic church. Today we have a pope that speaks out about it," John said.
"He is a compassionate, loving man who wants everybody to be included in the love of God. It is formidable what he is trying to do against many, many people in the church that oppose (him). He is courageous and he is fearless, and that's what we need in the world today," he added.