In his first Mass as pontiff, Pope Francis has displayed his informal style as a pastor. He delivered an off-the-cuff homily in the Sistine Chapel today about the need to walk with God, build up his church and confess. He referred at one point to children building sand castles on the beach.

Pope Francis delivers an informal homily (Servizio Fotografico L'Osservatore Romano via Getty Images)

It was a far simpler message than the three-page discourse delivered in Latin by his predecessor, Pope Benedict, during his first Mass as pope in 2005.

At the start of today's Mass, Francis spoke with the Vatican's master of liturgical ceremonies, Monsignor Guido Marini. Under Pope Benedict, Marini ushered in a far more traditional style of liturgy. Vatican officials confirm that Marini was somewhat put off by Francis' refusal last night to wear the formal papal red cape when he emerged on the balcony over St. Peter's Square.

The new pope's authorized biographer says the difference in style between Francis and his predecessor reflects his belief that the Catholic Church needs to be at one with the people it serves -- rather than imposing its message on a society that often doesn't want to hear it.