Rep. John Anderson, who has become the best known lay member of the Evanelical Free Church of America because of his presidential candidacy, has been criticized by the church's house organ for his liberal positions on abortion and gay rights.

An editorial in the April 1 issue of Evangelical Beacon, published at the denomination's national headquarters in suburban Richfield, Minn., was headlined "Anderson's position not Free Church.'" It was written by the magazine's editor, George M. Keck.

The editorial said that Anderson, who belongs to the First Evangelical Free Church of Rockford, Ill., "has the perfect right to express his convictions regardng abortion and other moral, social, economic and political issues."

"However," it said, "as (anderson) becomes more and more vocal in his proabortion stance, the Evangelical Free Church of America comes more and more in danger of being labeled, by association, of holding views similar to his on some key moral issues.

"It has come time to make it very clear that Rep. Anderson does not represent the consensus of opinion in the Free Church in regard to his prochoice views on abortion."

Anderson has supported abortion rights and signed a letter from the National Abortion Rights Action League, urging support for proabortion Democratic candidates.

He has also spoken in favor of laws to protect the rights of homosexuals. In particular, the editorial pointed to a telegram of support Anderson sent to a gay rights fun-raising banquet in Los Angeles in early March.

The editorial pointed out that the Free Church denomination had upheld the rights of the unborn child in a resolution adopted at its 1977 general conference and opposed homosexuality at its 1978 general conference.