The Post faults Congress for "tinkering" with the welfare system and not attempting to reform the benefit programs in a more fundamental way. "There is no consensus" on how to reshape the welfare system, The Post claims {editorial, July 22}.

I disagree. I am an original cosponsor of Sen. Daniel Moynihan's Family Security Act of 1987 precisely because it represents a consensus -- a consensus on how we can begin to reshape the system to make it more sensitive, helpful and efficient.

It isn't "tinkering" when comprehensive work programs are established to move welfare recipients off the rolls and into gainful employment. "A certain tameness" is not the way I would describe a new child-support enforcement system that would automatically withhold payments from an absent parent's paycheck and penalize states for poor performance in establishing paternity. The beneficiaries would be the poor children who otherwise would not receive support from the absent parent.

These are major steps in social policy. They re-flect values that have long been majority values -- the value of work, the importance of parental support -- but they have not been reflected in our welfare programs.

Moynihan and others who have worked on this proposal should be commended for producing a legislative package that rests firmly on these social values. A majority of mothers of young children are now in the work force, and that is the rationale for proposing that work or training for work be expected of welfare mothers and that child care needs be addressed. Mandatory work requirements accomplish another laudable goal: in some poor families no one has ever been employed.

The work program recommended in the Moynihan bill requires states to provide the service that is most basic to becoming employable: remedial education. The lack of a high school diploma and, more to the point, the inability to read and write are major deficits for many welfare parents who want to work.

The Post is right in noting that other changes might be desirable. Children's advocates, the state welfare commissioners and the governors have all called for equitable welfare benefits and a more rational system for figuring those benefits. The average three-person welfare family in Mississippi now receives $120 a month in AFDC benefits. Finding the will and the dollars to bring benefits in line with living costs will be an important part of this reform effort.

There is a strong consensus on many of the elements of Moynihan's bill. The long list of cosponsors proves the point: 22 Democrats and five Republicans, politically and geographically diverse, signed on as original cosponsors. Several of my Republican colleagues, including Sen. Robert Dole, have pledged to work on a bipartisan welfare reform package in the Senate Finance Committee.

It was President Reagan who gave the issue its visibility when he called for welfare reform in his 1986 State of the Union message. The Moynihan bill, in many respects, reflects the goals and values the president has long supported: strong families and work as a way out of welfare. It is my hope that a well-crafted, bipartisan bill emerging from Congress will gain the approval of the White House.

Throughout the country, states have made enormous strides in moving welfare recipients into private-sector jobs through innovative programs offering a mix of services ranging from basic skills education to sophisticated training. In Mississippi, 1,440 welfare clients were placed in jobs in 1985. With the federal commitment reflected in our bill, states can do even more to prepare welfare parents for independence from the system.

This country's poor families are now served by a fragmented welfare system that has outlived its initial purpose of maintaining widows and orphans. What we need now is commitment to act on the consensus we have reached. Contrary to The Post's view, we do know how to reform the system. The Family Security Act is an important first step. We must get on with it. -- Thad Cochran The writer is a Republican senator from Mississippi.