President Reagan sharply stepped up his campaigns for increased defense spending and against a nuclear freeze yesterday, telling a group of evangelical ministers that "simple-minded appeasement or wishful thinking about our adversaries is folly."

In a speech to the National Association of Evangelicals, in which he also reaffirmed his positions on abortion, prayer in schools and birth control for teen-age girls, Reagan urged the ministers "to speak out against those who would place the United States in a position of military and moral inferiority."

His remarks came as the House Foreign Affairs Committee, over his opposition, reported a nuclear freeze resolution to the House floor, and as the Senate Budget Committee prepared for a budget markup in which it is almost certain that his defense request will be heavily cut. Details on Page A7.

The administration is expected to continue its double-edged campaign for the defense budget and against a freeze today, when it will release new and enhanced estimates of Soviet military strength.

The president plainly was moving in his speech to re-energize the conservative base of support that helped elect him. He said proudly that his administration's "respect for the rule of law under God" leaves it "in opposition to, or at least out of step with, a prevailing attitude of many who have turned to a modern day secularism, discarding the tried and time-tested values upon which our very civilization is based."

One example, he said, was the so-called "squeal rule," under which the administration has moved to require that parents be notified when girls under 18 receive prescription birth control devices from federally funded clinics.

"I've watched TV panel shows discuss this issue," the president said, "have read columnists pontificating on our error, but no one seems to mention morality as playing a part in the subject of sex. Is all of Judeo-Christian tradition wrong?"

He said, "The fight against parental notification is really only one example of many attempts to water down traditional values . . . of American democracy."

The president then went on to note his support for prayer in schools and his opposition to abortion. He spoke out as well against racism and antisemitism in his list of essentially moral issues, then shifted to foreign policy and his view of the Soviet Union as an "evil empire."

"I believe we can rise to the challenge" of the Soviet threat, the president said. "I believe that communism is another sad, bizarre chapter in human history whose last pages even now are being written. I believe this because the source of our strength in the quest for human freedom is not material but spiritual. And because it knows no limitation, it must terrify and ultimately triumph over those who would enslave their fellow man."

In urging the evangelicals not to support a nuclear freeze resolution, Reagan said that the ministers must realize the danger such a freeze would pose for the United States.

"I would agree to a freeze," the president said, "if only we could freeze the Soviets' global desires. A freeze at current levels of weapons would remove any incentive for the Soviets to negotiate seriously in Geneva, and virtually end our chances to achieve the major arms reductions which we have proposed. Instead, they would achieve their objectives through the freeze.

"A freeze would reward the Soviet Union for its enormous and unparalleled military buildup," Reagan added. "It would prevent the essential and long overdue modernization of the United States and allied defenses and would leave our aging forces increasingly vulnerable."

Reagan inserted the comments about the nuclear freeze after the speech was written. He added that an "honest freeze" would be hard to achieve because of the difficulty in insuring effective verification and compliance with the treaty.

"Such a major effort," the president said, "would divert us completely from our current negotiations on achieving substantial reductions."

Reagan asked the ministers not to "ignore the facts of history and . . . simply call the arms race a giant misunderstanding and thereby remove yourself from the struggle between right and wrong and good and evil."