WASHINGTON, Nov. 13 — As Israeli bombs fell on Lebanon for a second week last July, the Rev. John Hagee of San Antonio arrived in Washington with 3,500 evangelicals for the first annual conference of his newly founded organization, Christians United For Israel.

At a dinner addressed by the Israeli ambassador, a handful of Republican senators and the chairman of the Republican Party, Mr. Hagee read greetings from President Bush and Prime Minister Ehud Olmert of Israel and dispatched the crowd with a message for their representatives in Congress. Tell them “to let Israel do their job” of destroying the Lebanese militia, Hezbollah, Mr. Hagee said.

He called the conflict “a battle between good and evil” and said support for Israel was “God’s foreign policy.”

The next day he took the same message to the White House.

Many conservative Christians say they believe that the president’s support for Israel fulfills a biblical injunction to protect the Jewish state, which some of them think will play a pivotal role in the second coming. Many on the left, in turn, fear that such theology may influence decisions the administration makes toward Israel and the Middle East.