According to Gospel tradition, the church stands on the site where Jesus performed the miracle of the multiplication of the loaves and fishes.
Israeli police detained 16 youth on suspicion of involvement in the incident but later released them. Ten of them could be yeshiva students.
Fr Matthias Karl, a German monk at the church, said a souvenir shop, an office for pilgrims and a meeting room were badly damaged last night, with bibles and prayer books destroyed.
“The fire was very active,” he said, but “The church, thank God is in good condition,” he added. “We’re very happy that nothing happened” to it.
“This morning’s outrageous arson attack on a church is an attack on us all,” Israeli Prime Minister Netanyahu said in a statement. “In Israel freedom of worship is one of our core values and is guaranteed under the law. Those responsible for this despicable crime will face the full force of the law. Hate and intolerance have no place in our society.”