Israel has declassified more than 30 secret orders made by government and military leaders, which it says rebut the charge that it committed genocide in Gaza, and instead show Israeli efforts to diminish deaths among Palestinian civilians.

The release of the documents, copies of which were reviewed by The New York Times, follows a petition to the International Court of Justice by South Africa, which has accused Israel of genocide. Much of South Africa’s case hinges on inflammatory public statements made by Israeli leaders that it says are proof of intent to commit genocide.

Part of Israel’s defense is to prove that whatever politicians may have said in public was overruled by executive decisions and official orders from Israel’s war cabinet and its military’s high command.

The court, the U.N.’s highest judicial body, began hearing arguments in the case this month, and is expected to provide an initial response to South Africa’s petition — in which it could call for a provisional cease-fire — as soon as Friday.

Since October, Israel has pounded Gaza in a campaign that has killed more than 25,000 Gazans, or roughly one in 100 residents of the territory, according to Gazan health officials; displaced nearly two million people; and damaged the majority of the buildings, according to the U.N. The campaign is a response to a Hamas-led assault that led to the deaths and abductions of roughly 1,400 people in Israel, according to Israeli officials.

The Genocide Convention of 1948, which South Africa has accused Israel of violating, does not define genocide solely as killing members of a particular ethnic or national group. Crucially, it says the killings must be committed “with intent to destroy” that group.

“Everything hinges on intent,” said Janina Dill, a professor at Oxford University and co-director of the Oxford Institute for Ethics, Law and Armed Conflict.

To that end, both South Africa and Israel are focused not only on what leaders and soldiers have done, but also what they have said. The roughly 400-page defense includes what Israel says is evidence that it sought a legal war with Hamas and not a campaign of genocide against the Palestinians.

Among the declassified Israeli documents are summaries of cabinet discussions from late October, in which Prime Minister Benjamin Netanyahu ordered supplies of aid, fuel and water to be sent to Gaza. He also instructed the government to examine how “external actors” might set up field hospitals to treat Gazans, as well as consider mooring a hospital ship off the coast of the territory.

Mr. Netanyahu’s most declarative statements were made in November, according to the released documents.

“The prime minister stressed time and again the need to increase significantly the humanitarian aid in the Gaza Strip,” reads one declassified document that Israel’s lawyers said was taken from the minutes of a cabinet meeting on Nov. 14.

“It is recommended to respond favorably to the request of the U.S.A. to enable the entry of fuel,” another document said.

On Nov. 18, according to the declassified minutes of another meeting, Mr. Netanyahu emphasized “the absolute necessity” of allowing basic humanitarian aid to continue.

But the dossier is also highly curated and omits most wartime instructions given by the cabinet and the military. The available documents do not include orders from the first 10 days of the war, when Israel blocked aid to Gaza and shut off access to the electricity and water it normally provides to the territory.

While the court could take years to reach a verdict, it may seek to impose “provisional measures” as soon as this week. Those measures could include a symbolic — and largely unenforceable — request for Israel to cease its attacks while the court deliberates.

To do so, the court’s 17 judges must find it plausible that Israel has killed residents of Gaza with the deliberate goal of destroying Palestinians as a group, according to international legal experts.

Actions that can constitute genocide can “be features of a war without being genocide,” Professor Dill said. “So it is really imperative to show this intent.”

Israel’s cabinet decisions could prove more relevant in several months, when the court begins to assess the merits of the case. The judges will need to decide whether Israel had no other motive to kill Palestinians aside from genocide, the experts said.

But at the current “provisional measures” stage, the experts said, the judges need only be convinced of the plausibility of South Africa’s claim in order to instruct Israel to suspend its campaign.

South Africa has tried to prove genocidal intent by citing more than 50 comments and statements made since October by Israeli leaders, lawmakers, soldiers and commentators.

Those cited include Yoav Gallant, the Israeli defense minister, who said Israel was fighting “human animals”; Amichay Eliyahu, the minister for heritage, who suggested dropping a nuclear bomb on Gaza; the country’s mainly ceremonial president, Isaac Herzog, who described Palestinians as “an entire nation out there that is responsible”; and Ghassan Alian, the Israeli general who oversees the distribution of aid to Gaza.

Israel has also submitted to the court a handful of emails between military officers and aid workers that it says shows its efforts to supply Gaza with food, medicine and vaccinations. Were Israel intent on the wholesale destruction of Gaza’s Palestinian population, the Israelis argue, it would not be working with the U.N. to distribute lifesaving aid.

One email, from a senior U.N. official to an Israeli officer overseeing aid distribution to Gaza, detailed an approved request to deliver solar-powered refrigerators to the territory to store vaccines and lab tests. A U.N. official confirmed the messages were authentic.

International legal experts said that the secret orders and emails provided important context, but that the court would regard them as one part of a wider picture.

Israel’s submission contained only a few of the decisions made by its cabinet and military leadership since October. The judges will need to assess whether or not the dossier tells the whole story of Israel’s plans, said William A. Schabas, an international law professor at Middlesex University, London, and the author of “Genocide in International Law.”

“When you’re trying to prove that you didn’t give an order to do something, obviously you’re going to show orders that indicate something else,” Professor Schabas said. “And if there is an order to do something or a plan to do it, you’re not going to provide that.”

Orders to provide sufficient humanitarian aid to Gaza would also need to be assessed against what Israel has actually allowed to happen on the ground, Professor Schabas said.

“Things that appear to be directed at sustaining life don’t necessarily disprove the opposite,” he said.

The United Nations, for example, recently accused Israel of blocking aid to north Gaza, a charge Israel denied. The U.N. has also warned of a looming famine amid food shortages and the collapse of Gaza’s health system.