When John Richard Keating was growing up, he couldn't abide the spaghetti that was standard fare at the Keating household for meatless Fridays.

But seven years in Rome as a seminarian and later a graduate student changed all that for the future Roman Catholic bishop of Arlington. "In Rome, you had pasta seven days a week, and I got to love it," he recalled.

He loved it so much that he learned to cook it and a few months ago appeared on a Chicago television cooking show demonstrating the proper way to cook pasta.

Cooking with an Italian accent has become one of Keating's hobbies. He honed his skills, he said, "when one of the parishes to which I was assigned lost a cook, so I took over for a while." His prize dish, he said, is chicken cannelloni.

It is not entirely clear when he has had the time to indulge in any of his hobbies--he is a church history buff, maintains what an associate describes as a "modest" model train collection, and plays an occasional Wednesday afternoon round of golf.

Throughout most of his church career in Chicago, Keating, who will be 49 next month, served both as an assistant pastor in a variety of parishes and as a church bureaucrat for the massive Chicago archdiocese.

After completing doctoral studies at the Gregorian University in Rome in 1963, Keating became assistant chancellor of the Chicago archdiocese. He was cochancellor before being named to his present post of chancellor and vicar general of the archdiocese.

At the same time he served on several committees and related agencies, including the priests' senate, the clergy personnel board and the archdiocesan tribunal. For a decade he was a consultant to the National Conference of Catholic Bishops' committee on canonical affairs.

In the Roman Catholic Church, bishops are selected and assigned by the pope, on the recommendation of the apostolic delegate or other representative in the country involved.

Some church observers say they saw the handwriting on the wall, as far as Bishop-elect Keating is concerned, last summer. During a gathering in connection with the installation of Cardinal Joseph L. Bernardin as archbishop of Chicago, Apostolic Delegate Pio Laghi was particularly lavish in his praise of Keating, who had been elected by his fellow priests as administrator of the Chicago archdiocese after the death of Cardinal John P. Cody.

To those attuned to the fine nuances of Vatican politics, such praise seemed to be almost an anointing. It was only a matter of finding the proper opening.

Keating said he first learned of his selection to head the Arlington diocese through a phone call from the delegation office on Memorial Day notifying him of the appointment and asking whether he would accept it.

The relatively young Diocese of Arlington, to which Keating goes, has spent a fair amount of its nine years in the eye of the storm that has swept the worldwide Catholic church after Vatican II. The generally conservative orientation of Keating's predecessor, Bishop Thomas J. Welsh, pleased many in the diocese.

But there were others, particularly among the laity, who wanted to move further and faster in implementing Vatican II ideas than Welsh was prepared to go. Conflicts reached all the way to the Vatican.

In a telephone interview, Keating gracefully sidestepped a question as to whether he was a liberal or a conservative, but observed mildly, "Yes, I understand there is some interest in that" in his new diocese.

The new prelate is a tall man who carries himself with an athlete's grace. His dark hair is beginning to gray at the temples, and, according to a Chicago colleague, Keating "is considered pretty good looking."

Keating, who is formally known as John but whose friends call him Dick, has not been to Arlington, he said, since his days "as a high schooler," on a trip to the nation's capital.

He plans to make a flying visit next Thursday, for a quick look around the diocese, he said. At the moment there are no plans for a public meeting at that time.

By his own self-assessment, the new bishop believes that the major strengths he brings to his new post include his continuing involvement with local parishes during the 21 years he spent in church administration.

"The parish experience is important to me," Keating said. "I've not been totally involved in office work."