In pictures: Pope in Nazareth

Pope John Paul II celebrates mass in the Basilica of the Annunciation, on the site where Christians believe the Angel Gabriel appeared before Mary, the mother of Jesus.

The pontiff urged Christians to defend the family, and all people to respect the dignity of others.

The grotto where Gabriel appeared to the Virgin Mary

The 79-year-old pontiff appears to tire during mass

Worshippers pack in for the invitation-only mass

Celebrating communion in one of Christianity's holiest sites

A police officer stands guard for the Pope's arrival

A boy waves a flag emblazoned with the Pope's image