AREA CHURCHES report a sharp increase in the number of people seeking emergency charity in the form of food or cash. As reported recently in this newspaper, the daily line at one soup kitchen has increased from 200 a few years ago to 600 today; the crisis intervention program of the Catholic Charities helped 40 people per month last summer, and now sees almost 100. The pattern is repeated nationwide.

It's easy to miss all of this if you live and work in affluent neighborhoods and pick your commuting routes carefully. But churches and other private charities, particularly those based in the midst of the greatest woes, feel very much on the front lines of this recession -- they are embroiled in the trench warfare of economic policy, and it is quite different from the high drama of strategic warfare in Capitol Hill conference committees. The fluctuations in the length of soup lines do not make headlines with the same depressing regularity as the familiar bloodless statistics about housing starts, retail inventories and the prime interest rate.

Charitable activities deserve much credit and appreciation for their continuing accomplishments. However, this should not lead anyone to make a rosy assessment of President Reagan's scheme for increased reliance on voluntarism as a means of salving widespread social and economic trauma. The fact is that many of these agencies are at or beyond their capacity to help. In part, that's because times are so bad, with the highest unemployment rates since Pearl Harbor finally cured the Great Depression. In part, it's because the decades of an expanding welfare state, combined with an expanded standard of communal rather than individual generosity, have led people to depend on the government to provide what earlier generations imagined was being provided by charity.

And in part, care-giving institutions are strapped because the poor continue to line up at their local churches in Shaw and Anacostia, rather than commute to the posh parishes in Chevy Chase and Great Falls. And the long, long lines at the District's unemployment offices, which begin forming well before dawn, are well out of Congress' sight.

Perhaps the District government should rent space in the new Senate office building to house an unemployment office and a soup kitchen. And the House could donate space to shelter the burgeoning number of evicted homeless families. Who knows? It could have a bracing effect on the legislators: it might even do some good where their voting is concerned.