The new archbishop of Canterbury on Monday formally took up his post as the leader of the world's 80-million-strong Anglican Communion.
The Most Rev. Justin Welby swore allegiance to the queen as he accepted the position amid prayers for him, his wife Caroline, and their five children.
The election of the 57-year-old Welby, a former oil executive, comes at a difficult time for the Anglican Communion, whose global membership includes the U.S. Episcopal Church.
The communion has been riven by bitter disagreements over female bishops and church teachings on gay relationships. Welby reiterated Monday that he backed the Church of England's opposition to government proposals to introduce gay marriage.
Welby succeeds Rowan Williams, who retired in December after a decade in office.