In "Christianity for Convicts" [letters, Nov. 30], Paul Mathieu argues that the program of fundamentalist Christian conversion for convicts is like "re-education" programs in Communist countries. And he asserts that "the encroachments of Christian fundamentalism in our society are cause for concern," particularly when they supply "captive audiences."

The program, Inner Change, which has been endorsed by Gov. George Bush and Vice President Al Gore, is voluntary. The "audiences" are not "captive," as some in counseling programs are, and the program, according to a Post story of Nov. 27, seems to be helping convicts to live useful and productive lives after release. If Christianity can help to reform convicts, as it has helped many others, why not try it?

If Inner Change differs from counseling, which Mr. Mathieu may approve, it differs principally in assuming the need for influences and assistance that are beyond the personal and social, as Alcoholics Anonymous and similar programs assume in their successful efforts at rehabilitation. Finding gainful employment is, as Mr. Mathieu observes, an important condition for the successful social integration of former convicts. But without a change of moral purpose, employment alone will not solve the problem of recidivism.

As for the "encroachments of Christian fundamentalism," those are the consequences of the free exercise of proselytizing under the First Amendment. If they are persuasive to many, that is their merit. The same freedom to proselytize is open to all, religious, non-religious, anti-religious. Surely Mr. Mathieu would not selectively prohibit or abridge the right of Christian conservatives to do so.

JOHN ILLO

Shippensburg, Pa.