President Reuven Rivlin of Israel, a veteran of the ruling conservative Likud Party, eulogized Mr. Avnery on Monday, describing him as having “a special status as an eternal oppositionist.”

In a Twitter post, Mr. Rivlin said that Mr. Avnery’s “battles for the freedom of expression paved the way for Israel as a young state.”

“We had sharp differences of opinion,” Mr. Rivlin added, “but they were dwarfed by the aspiration to build a free and strong society here.”

In his lifetime Mr. Avnery journeyed rapidly across the Zionist political spectrum. With the rise of Nazism, he had immigrated from Germany to British-mandate Palestine with his family in 1933, at the age of 10. At 15 he joined the Irgun, the right-wing underground militia, which fought both the Arabs and British forces in the struggle to establish the state of Israel.

Like Mr. Rivlin, he was inspired by Zeev Jabotinsky’s uncompromising school of Zionism. He remained in the Irgun until 1941, but became disenchanted with its methods and ideology.

By the 1948 war, when five Arab countries attacked the emerging state and Mr. Avnery fought and was wounded, his perspective had fundamentally changed.

“What in my eyes is the great success is that I and my friends raised for the first time the principle that there is a Palestinian people with whom we have to make peace at the end of the 1948 war,” he told an Israeli interviewer a few years ago, adding: “I don’t think there were 10 people in the world that believed in this. Today it is a world consensus.”