President Reagan asserted twice yesterday that U.S. arms spending is sanctioned by Scripture and said defense budget cuts would weaken the nation in the face of the "unprecedented military buildup of the Soviet Union."

"You might be interested to know that the Scriptures are on our side in this," Reagan told a group of business and trade representatives in the White House. "Luke 14:31, in which Jesus in talking to the disciples spoke about a king who might be contemplating going to war against another king with his 10,000 men, but he sits down and counsels how good he's going to do against the other fellow's 20,000 and then says he may have to send a delegation to talk peace terms."

"Well, I don't think we ever want to be in a position of only being half as strong and having to send a delegation to negotiate under those circumstances -- peace terms -- with the Soviet Union," Reagan continued.

Later in the day he cited the Biblical passage again in a speech to the National Religious Broadcasters Conference meeting at the Sheraton Washington hotel.

"I don't think the Lord that blessed this country as no other country has ever been blessed intends for us to someday negotiate because of our weakness," the president said.

In this speech, where Reagan also invoked "Divine Providence" in behalf of his proposed domestic budget cuts, he paid tribute to the "relevance of religion in the modern world" and cited religious symbols that could be seen from the White House during December.

One of them was "the huge Menorah celebrating the Passover season in Lafayette Park," he said. Actually, the Menorah, a ceremonial candelabra, is the symbol of Hanukah, the Jewish festival of lights.

This misstatement was written into the president's text. However, Reagan departed from his prepared speech to make the Scriptural argument for defense spending.

The Scriptural passage quoted by Reagan read: "Or what king, going to make war against another king, sitteth not down first and consulteth whether he be able with ten thousand to meet him that cometh against him with twenty thousand? Or else, while the other is yet a great way off, he sendeth an ambassador and desireth conditions of peace."

In context, the passage's point appears to be that half-measured preparation and commitment are not sufficient. It continues: "So likewise whosoever he be of you that forsaketh not all that he hath, he cannot be my disciple."

In his speech to the business and trade representatives Reagan expanded upon the initial part of the passage with an analogy to the upcoming arms control talks with the Soviet Union.

"Ultimately, our security and our hopes for success at the arms reduction talks hinge on the determination that we show here to continue our program to rebuild and refortify our defenses," the president said.

He also made a more traditional argument in this speech and another to new members of Congress, saying that "the defense of our nation is the one budget item which cannot be dictated solely by domestic considerations."

Reagan asked the religious broadcasters for support of the budget he submitted to Congress yesterday in an appeal that mixed religious fervor with some typical presidential humor.

"There is a real and heartfelt reason why I'm here today," Reagan said. "I just sent the budget to the Congress and I hope that in spirit, at least figuratively, we can all from here on in have our hands joined in prayer."

The remark drew laughter from the broadcasters, who applauded the serious message of his speech and punctuated his call for greater religious involvement with cries of "Amen."

"You have fought the good fight for prayer in the schools and against abortion and for freedom in the world," Reagan said.