Carlos Van Leer is a man with a message, and a modern medium to get it across--a telephone answering machine. Showcasing "religious causes as entertainment" is his objective, and last month marked 10 years worth of tape-recorded tidings designed to provoke, inspire and enliven the caller's day.

Van Leer, 75, approaches the issues "not with the robe of a priest, not with a Bible in hand, but with deep religious dedication, and a touch of the clown," he says. Often he puts new words to old tunes, such as this version of the Straw Man's song in the Wizard of Oz: We would hope Ground Zero hinders Turning children into cinders Our own offspring down the drain We would be a trifle wary Of solutions military If we only used a brain.

Songs like these and other commentary on current events, Van Leer estimates, comprise the estimated 3,500 messages that have been heard by--at the last check of the device's counter--382,000 callers since the first recording was played June 5, 1972, in his Bethesda home.

Through the recordings, Van Leer hopes to stir people to act in a constructive way on today's "basic issues." As a former salesman of insurance and medical supplies, he knows that "you have to help people see that it is to their advantage" to do so.

"We human beings have been given by the Creator perfectly extraordinary potentials and we're scared to use 'em," he says.

Although Van Leer now tackles the big issues, he started the recordings to help save the Chevy Chase Lake swimming pool from developers who planned to build nearby. The pool wasn't saved but did remain open last summer, and through that experience Van Leer glimpsed his machine's potential to reach people without costs for postage, mimeograph supplies or gasoline.

In 10 years' time, Van Leer has addressed numerous subjects but often focuses on peace and human rights, particularly supporting the causes of women, minorities and the poor.

His reputation is so widespread that Van Leer never found it necessary to list his number--652-1556-- which has been in almost continuous use for a decade. In the process, Van Leer has "worn out" two recorders, and his third can accommodate a "practical maximum" of 700 calls a day, one at a time, before the "machine is just about smoking," he says. Calls average around 50 or 60 a day, with occasional dramatic jumps.

"Carlos is a bit of a troubadour," says the Rev. Ted Lockwood, an Episcopal priest associated with St. Stephen and the Incarnation Church at 16th and Newton streets NW, where Van Leer is a member. "He's not an organization person, but he fits in in his own way to the church" very nicely, Lockwood says, adding that Van Leer's creative approach has helped advance church concerns with peace and social action.

"The peace movement is losing its effectiveness in the most horrible way by not being innovative," says Van Leer. "Where's the excitement?"

A perennial protester who's likely to turn up at any kind of liberal demonstration, Van Leer invariably attracts cameras and reporters with a one-man show that includes buttons like "Send in the Clowns" and "Celebrate Life!" and a repertoire of songs accompanied by what he calls his "strolling jester's organ" with portable amplifier.

Van Leer says he acts the clown to help "pull down the tension" and his recordings are part of that effort.