A Montgomery County Circuit Court judge, in a rare public display of judicial humility, apologized yesterday to former Securities and Exchange Commission enforcement director John M. Fedders for tagging him a "manic-depressive" in open court in February during a divorce hearing.

Judge James McAuliffe also granted Fedders, 43, a four-month delay in divorce proceedings and refused to grant his wife Charlotte, 41, an increase in alimony and support payments for the couple's five sons.

According to testimony in the divorce case, Fedders, a 6-foot 10-inch former Marquette University basketball player, repeatedly beat his 5-foot 9-inch wife during their 18-year marriage and ran up huge debts trying to live like a wealthy lawyer despite a government salary.

Charlotte Fedders sobbed softly during yesterday's brief hearing and avoided returning her husband's gaze. McAuliffe reset the case for Sept. 23 and 24.

Publicity surrounding the case lead to Fedders' resignation as SEC enforcement director on Feb. 26. Earlier this month, Fedders joined the Washington law firm of Miller, Cassidy, Larroca & Lewin as a partner at an undisclosed salary. One of the firm partners, Nathan Lewin, represented Fedders while he was a subject of a federal investigation into an alleged cover-up of a bribe scheme by Dallas-based Southland Corp., which Fedders had represented before joining SEC in July 1981.

After hearing testimony on Fedders' professional excellence and on the domestic violence, McAuliffe had speculated from the bench in February that Fedders was a "manic-depressive."

Yesterday, McAuliffe told Fedders he was sorry for any "hurt" the remark had caused. Then McAuliffe denied Charlotte Fedders' request to proceed with the divorce trial, citing the couple's "uncertain" finances. McAuliffe also denied her request for an additional $1,000 a month to supplement Fedders' $1,200 monthly payment to maintain the family in its $285,000 Potomac home.

Fedders would not comment yesterday on whether he had sought the delay in an effort to try to reconcile with his wife. Charlotte Fedders hurriedly left the Rockville courthouse after the proceedings without comment.