All that could be seen of Mariam Shalaby was her face, wrapped in a yellow headscarf and peeking above the lectern, as the 11-year-old from O'Hara led 250 Jews, Christians and Muslims in a prayer for peace inside St. Paul Catholic Cathedral in Oakland.

She asked God to grant "peace to you all, to the G-20 summit and to the universe."

The prayer service, among numerous other G-20-related religious events, was organized by Christian Associates of Southwestern Pennsylvania and the Religious Leadership Forum of Southwest Pennsylvania. Another interfaith service, with groups as diverse as Buddhists and Zoroastrians, was held simultaneously on Mount Washington.

The service in St. Paul Cathedral was built around shared traditions within the three faiths that trace their roots to the patriarch Abraham. A Lutheran compline choir sang psalms in the Catholic cathedral, as the gathering brought together many factions. There were Jewish men with and without yarmulkes, Muslim women with and without veils and representatives of the two Episcopal Dioceses of Pittsburgh that are in litigation against each other.

Bishop David Zubik welcomed everyone to his cathedral. "Without ignoring our differences or hiding our most fervent beliefs," he said, they had gathered "to praise our God and beg his help in a very special moment in the history of our city."

Nico Satryan, a junior at Winchester-Thurston Academy, sounded the shofar. There were readings from the Hebrew scriptures in Hebrew and English, from the Christian scriptures in English and Korean and from the Quran in Arabic and English. Representatives of each tradition gave prayers and reflections.

Karen Hussaini, founder of the Syed Farooq Hussaini Interfaith Network -- which carries on her late husband's dedication to interfaith relations in Pittsburgh -- spoke of the 23,000 children who die each day due to poverty.

"It is by God's mercy alone that we live in a nation of economic wealth and prosperity, where we are free to speak our minds, where we are free to worship as we desire," she said.

Afterward, Matthew Craig, a Catholic from Squirrel Hill, said the service was itself an answer to prayer.

"It would be such a gift to the world if the G-20 leaders could come and find a prayerful experience here in Pittsburgh. Wouldn't it be significant if they found something different here, where peace was lifted up in prayer? What better way could we welcome the world?"

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