Christians around the world are observing Good Friday, which commemorates the crucifixion of Jesus.
Many Christians attend services Friday to pray and reflect on the execution of Jesus near Jerusalem nearly 2,000 years ago.
Christians believe Jesus returned to life on what is now observed as Easter Sunday.
Pope John Paul II - the leader of one billion Roman Catholics - has been limited in Holy Week activities this year as he recovers from a throat operation last month. He will not lead public ceremonies today as he has in the past.
President Bush, a devout Protestant Christian, issued his Easter greeting Friday, saying the teachings of Jesus "continue to comfort and strengthen Christians around the world."
Orthodox Christians commemorate the occasion next month.