One of the first and most important lessons of journalism, whether you learn it in school or in a newsroom, is the one about not losing your objectivity. Don't like anyone too much; don't dislike anyone too much.

Last Tuesday morning, when I heard Ed Thomas was dead, I knew I had broken the rule.

Ed Thomas was a politician, a state senator from Frederick County, a devoted Republican and a man I covered for almost a year in the General Assembly and during the 1982 Maryland campaigns.

As a reporter, you meet dozens of people and, because you are human, you like some more than others. But always in your mind is that warning about keeping at arm's length.

But it was difficult to remain objective where Ed Thomas was concerned. Before he died, he underwent nine operations during a 3 1/2-year battle with cancer. No one, even those close to him, can remember hearing him complain. His sense of humor never wavered and somehow, even through the pain of chemotherapy, the operations, the constant trips to the doctor's office, not to mention the specter of death over his shoulder, he always seemed convinced he would beat the disease before it beat him.

When I first came here last year, the first politician I met was Thomas. He recognized my name from the sports pages because he was a fanatical University of Maryland sports fan. Because of that as much as anything, he seemed to feel a responsibility to try to help the kid out.

Every now and then he would sidle up to me in the Senate hallway and say, "Something's about to happen here," and point me in the right direction. When I would thank him, he would clap me on the shoulder and say, "Hey, us old jocks have to stick together, right?"

Thomas was an old jock; he was also an old newspaperman, having written sports in his early days. If he had a weakness as a source, it was that he was so honest and helpful that any reporter who knew him and called for help, got it. Reporters prefer sources with biases--towards them.

Last winter, Thomas really looked as if he had won his fight. Much of his weight and color had returned, and he was as active as anybody during the session and the campaigns. He tried desperately to steer Republican gubernatorial candidate Robert A. Pascal away from the disastrous course he eventually charted for himself.

One morning he took Pascal to breakfast and yelled at him for an hour. The next day Thomas got a note, "Thanks for straightening me out . . . . Bob." That talking-to only lasted a couple of weeks.

When someone dies, there's always a tendency to remember the last time you saw him. With Thomas, that memory is particularly vivid. It was in December, a couple of weeks before the session was supposed to start. He had just had breakfast with new Senate President Melvin A. Steinberg to tell him, as the minority leader, what committee assignments he wanted.

Thomas knew he was returning to the hospital, but he promised to be back in Annapolis before the session even started.

If he was scared, as all his friends were, he never showed it. By the time the session began, he had undergone two more operations and, quietly, the word was passed that the prognosis was not good. The two senior wire service reporters at the State House both knew they should prepare an obituary. Neither had the stomach for it.

During the last six weeks, even as he got sicker and weaker, Thomas kept in touch with friends in Annapolis. He dropped them notes, talked on the phone when he could. In mid-February, a note arrived in the press room addressed to all the media. It was a thank-you for the flowers that had been sent.

Ed Thomas once said that the reason you ran for reelection (his margin of victory grew larger each of the four times he ran) was so you could come back to Annapolis and party with your friends. No one liked a beer and his buddies more than Thomas, and those friends, right until the end, held out hope. "If anyone can make it back, Ed can," they said again and again.

Last May, when his colleague Edward T. Conroy was lying in a hospital bed dying from the same disease that would eventually kill Thomas, he called Conroy to try to convince him to take chemotherapy. The pain, Thomas argued, was worth it if it kept you alive.

Sen. Charles (Buck) Smelser, his close friend, said it best: "No one loved living more than Ed Thomas."

He was 54 when he died. And so, last Tuesday morning, walking through the rain, I forgot my journalism lessons, and I stopped fighting the tears.

Ed Thomas was worth a good cry.