This is a most difficult time for President Reagan. He is being pushed by financial crisis to a tax policy he abhors, and by the logic of diplomacy toward a superpower summit that his conservative adherents oppose. Encouraged by Attorney General Edwin Meese III, he has unwisely opened a second front with the Senate on another controversial Supreme Court nomination. The prospects for Reagan's declining presidency do not seem bright.

But the strain of these public conflicts are secondary to the president, whose private life has become rimmed by the sorrows of First Lady Nancy Reagan. The Reagans are close beyond any normal measure. He spent much of October comforting Nancy Reagan during her battle with cancer, as she had comforted him. He told her of the death of her mother. Although he hates to fly, he flew with her to Phoenix and returned by himself that night because he had work to do the next day. At week's end, he flew back to Phoenix to help his wife mourn Edith Luckett Davis, who had also been a friend to him.

Throughout most of his life, Reagan has comforted others in time of sorrow. "Love is never wasted, love is never lost," he told the weeping families of 248 American servicemen who died in a Newfoundland plane crash in 1985. But that was a public event. It is more important to know that Reagan regularly writes letters and makes telephone calls to persons who have lost loved ones, even when the cameras are not rolling.

In two decades of writing about Reagan, I heard occasionally after some tragedy that he had telephoned or written a person he never knew. The disclosures usually came from the recipients of these calls and letters, for Reagan made it a point not to publicize them. I made notes and stored the information, as journalists are trained to do. We always think that the bell tolls for someone else.

When my mother died several years ago, the president called to offer condolences. I thanked him and said that her death had been expected and that, while I thought I was prepared for it, I had really been hit quite hard. "You are never prepared for the death of your mother," he said softly. It seemed to me -- then and now -- about the most sensible and kindly thing that could have been said. It also struck me that Reagan was talking in a different voice without a script and that he was more compelling than he had ever been on stage.

Reagan reminisced about his mother in the State of the Union address last February. Horace Busby observed that this was rare for Reagan in a public speech, "unlike other presidents who have summoned up memories of their mothers with little provocation. This underscored what is often overlooked: He has been, by far, the most private of presidents, allowing little to be known of him."

Perhaps one secret of Reagan's political success over the years is that this private Reagan comes through somehow to Americans in ways that are imperfectly understood. I don't know. I do know that Reagan, who has spent most of his life in the spotlight, is an astonishingly private person who conceals his grief and does not take counsel of his fears. It must cost him a lot in this time, when his wife is suffering and his friend Mike Deaver is on trial. One wonders sometimes if even Reagan's huge store of optimism and self-reliance is large enough to keep him going.

Reporters are taught to set aside their feelings. At the Reagan White House, if they work for television networks, they also learn the art of shouting questions at a president who seeks to avoid answering them. This art form, not particularly ennobling for the presidency or the press, is complicated further by Reagan's hearing difficulties.

As the president left for Phoenix last week, CBS White House correspondent Bill Plante, usually a most resolute questioner, shouted "condolences" to Reagan. Others joined in. The president, thinking that they were shouting questions about the summit, kept walking. Later, when an aide explained to him what had happened, he laughed about it and was pleased that others cared enough to comfort him. He is in need of that now. It is a most difficult time for the Reagans.

Reaganism of the Week: Receiving a report on the status of small business last Thursday, the president said: "Recently, there have been some signs of economic concern. The fact is the stock market, even after these last weeks of adjustment, is still much more than double what it was in August of 1982."