President Carter told a House subcommittee at the white House yesterday his new welfare plan will guarantee a job to every needy family whom it requires to work. This was contradicted by his Labor Secretary, Ray Marshall, several hours later.

The discrepancy produced some spirited questioned of Marshall at the afternoon session of the subcommittee which opened hearing this week on the welfare plan.

"This morning the President indicated that this program guaranteed a job to every family in the category." Rep. Charles B. Rangel (D-N. Y) announced to Marshall who had not attended the White House meeting.

"We believe it's almost a guarantee," replied Marshall.

"The point is, Mr. Secretary, we want the President's statements to hold water," Rangel said, "so if we trust the President why won't you? . . .

Why can't we make the President's word part of the bill and say families . . . who want to work will be guaranteed a job?"

Marshall replied he would have to check with the President before answering that question. He had said earlier that cost was the main reason for not putting in such a guarantee.

The jobs portion of Carter's program, one of it's most controversial elements would create 1.4 million full and part-time public service jobs for the heads of families with children that can't find any other work.

One of Marshall's aides Jodie Allen, told the subcommittee earlier that "we have arbitrarily limited the number of those jobs for cost reasons." She said the department believes there will be "a much greater demand" for the jobs than the department can meet.

Subcommittee members also hammered away at Marshall on two other issues: why most of the jobs would pay only the minimum wage and why the parents of children over age 6 would be required to work while single persons and childrens couples would not participate in the jobs portion of the plan.

A Department of Labor fact sheet said that raising wages would "trigger a rapid increase in the costs and administrative burden of the program."

The department's figures indicated that a 10 per cent rise in the wage would trigger a 20 per cent greater demand for the public service jobs, the fact sheet said.

Rep. William M. Brodhead (D-Mich.) said he was concerned about how the work requirements would affect families.

The plan requires at least one person in a family to work part-time if their family children are ages 6 to 13, and full-time if their children are 14 or over.

In an impassioned plea. Brodhead said there are "hundreds of thousands of children" over age 14 "who require the presence of a full-time parent in the home . . . at the same time there's a childless couple down the street who has all the time in the world, and yet are forbidden to take one of these jobs . . ."

He said he was particularly concerned about children over 14 who may be chronic truants, or chronic troublemakers.

"Let me say you've raised a very important point," Marshall replied.

"I think you're going to have to do better than that, Mr. Secretary," Brodhead responded." . . . We have to recognize that the care of children is the most important work there is."

Marshall said he would see whether the plan could be changed to reflect some of Brodhead's concerns.

Health, Education and Welfare Secretary Joseph A. California Jr. attended the meeting with Carter, and told a news conference later be hopes the subcommittee can draft a set of new welfare plan principles by Christmas, and then go to work on a bill early next year.

That schedule represents a slipping of the administration's original time-table which called for the subcommittee to produce a bill by the Christmas