If you listened to the debate in the House this week, you might have thought that the Visigoths had invaded the Capitol. Cries of rape, pillage, trampling, looting, well poisoning and the rending of the "special fabric that holds us together" filled the chamber.

Over in the Senate, there was similar lamenting and breast-beating among the Democrats, although the terminology was less lurid and there was no accompanying guerrilla theatre.

On both sides, "comity" was reported to be on life-support systems.

What was the trouble? Why had so many strong men and women succumbed to self-pity, proclaimed themselves to be feeling disillusioned, disenfranchised and generally hopeless about their ability to go on.

It was the tyranny of numbers.

In the House, the issue was the election in the 8th District of Indiana, which has the name of the "bloody 8th" because it has proven in recent years to be the most volatile patch of political real estate in America.

In 1982, the seat was won by a liberal Democrat, Frank McCloskey, 45, a former newspaperman and one-time mayor of Bloomington. Last November, he and a 28-year-old conservative state legislator, Richard D. McIntyre, ran so tight a race that the results were delayed for weeks. After the first recount, McIntyre was held the winner by 34 votes. Democratic suggestions for a special election elicited only Republican scorn.

House Speaker Thomas P. (Tip) O'Neill Jr. (D-Mass.), with the matter still in dispute, refused to seat McIntyre, on the grounds that House comity, which was then in operation, would predispose his colleagues in his favor. The speaker appointed a task force, chaired by Rep. Leon E. Panetta (Calif.), a Democrat whose probity had not been questioned. After a recount, the task force decided that McCloskey had won by four votes.

From the beginning, the right-wing House Republicans, led by Newt Gingrich (Ga.), Robert S. Walker (Pa.) and other C-Span Commandos who equate moderation with wimpiness, have made it a holy war. They conscripted the usually go-along leader, Robert H. Michel (Ill.), and the party united in outrage. While they never actually threatened to throw themselves on the House carpet and hold their breath until the Democrats said uncle, they went to infinite pains to dramatize their displeasure, denouncing Panetta and the speaker for thievishness and thuggery.

McCloskey, a quiet, intense man whose heroes are Thomas Merton, Robert F. Kennedy and Hugo Black, said he knows he can survive the Republican hazing that is still in store.

"I don't take it personally," he said.

He admitted that some Democrats -- in addition to the 19 who voted against accepting the Panetta report -- had told him privately that he would be better off to accede to a special election. But he insists that neither he nor McIntyre wanted to to through it all again.

He thinks that the Republican tantrums will redound against them. The Chicago Tribune has accused them of acting like 2-year-olds.

And since the disruption will mean delay in enacting the handiwork of their president, the Republicans are expected to settle down. In spite of all they said and did, including a formal walkout, McCloskey was sworn in. And Michel and GOP Whip Trent Lott (Miss.) gave comity a reprieve by returning to the chamber to shake his hand.

Meanwhile, Democratic senators dealing with the Reagan-Republican Senate "compromise" budget had no better luck with their plaints and their wordier warnings that heavy-handedness is fatal to comity.

Minority Leader Robert C. Byrd (D-W.Va.) and Sen. Lawton Chiles (D-Fla.) heaped hot coals on the head of Majority Leader Robert J. Dole (R-Kan.). Surely, they said, he would not misuse his power. Surely he would follow the tradition of recognizing whomever was up first and not recognize, instead, someone he had already chosen to offer an amendment.

Dole was careful never to get their point. He knew that what they were really telling him is that it would be grossly unfair to deprive Democrats of the glory of saving the Social Security cost-of-living adjustment increases that President Reagan wishes to cut. There was no question that the COLAs would be restored -- 22 Republicans are up for reelection.

The only question was whose name would be on the amendment of salvation. Of course, Dole saw to it that one offered by two Republicans was the one that passed easily.

It's a sad thing to be a Democrat in the Republican Senate, as sad as being Republican in a Democratic House. It means talking a lot about comity.