Sixty years ago, when little boys took lessons in elocution, the custom was to memorize great chunks of heroic poetry. It fell to one little boy to declaim, with appropriate gestures, the ballad of Horatius from Macaulay's ''Lays of Ancient Rome.''

The boy fell to thinking of Horatius the other day. Actually the lad, now old and gray, was thinking of George Bush. The president seemed to be retreating from his promise to approve ''no new taxes.'' Pressures upon him were mounting from every quarter. Without a substantial increase in taxes, the president was told, deficits would soar, interest rates would climb and disaster would be close at hand.

So it was when ruin threatened Rome. ''Then out spake brave Horatius, the captain of the Gate: To every man upon this earth death cometh soon or late. And how can man die better than facing fearful odds, for the ashes of his fathers and the temples of his Gods?''

The story turned out happily: ''With weeping and with laughter, still is the story told, how well Horatius kept the bridge in the brave days of old.''

Mr. President, stand like Horatius! Hold firm to your convictions! Don't yield now! If a tax increase can be averted for the next three years, and if Congress will restrain its impulse to spend the dividends of peace, natural growth in the economy will bring the budget close to balance. We are now on what some economists call a ''glide path,'' as the rate of increase in revenues approaches the rate of increase in spending. Hold to a steady course!

Political considerations clearly support a policy of firmness. If Bush made one position clear during his campaign, it was his position on taxes. ''Read my lips!'' He made it a litany. ''Read my lips! No new taxes!'' This was a pledge of honor, and Bush is an honorable man. His steadfast opposition to a tax increase was the most important element in his successful run for the White House.

To be sure, if some overwhelming situation should develop, the trusting voters would forgive him a retreat. No such calamity is in sight. The bailout of savings and loan depositors can be paid for over the next 30 to 40 years. The same thing is true of the obligation to rebuild bridges and to fight the war against drugs and crime. Continued large deficits are a problem, but they are not a desperate problem.

Let us keep key figures in perspective. The size of the deficit, whether quoted in current dollars or constant dollars, is not the figure that matters. What matters is the deficit as a percent of our gross national product. A homely analogy may be found in personal debt. The family with a $20,000 income and a $100,000 mortgage is in trouble; the family with the same mortgage and an income of $100,000 is relatively secure. This year the deficit will amount to only 2.3 percent of GNP. This is the lowest figure in 20 years.

Do not think the unthinkable, Mr. President! Be like Horatius! Or be like Ulysses, who ordered sailors to bind him to the mainmast lest he succumb to the sirens' song. Take your model from the boy who stood on the burning deck, whence all but he had fled. The old heroic ballads speak to us through the ages.

This is a time for leadership. It is what presidents are expected to provide. The budget that Bush sent to Capitol Hill in February constituted no leadership at all. If the president were now to call simply for a freeze on outlays at the current level, the country would rally to his support. He would enlist such powerful allies as Rep. Dan Rostenkowski of Illinois and Sen. Fritz Hollings of South Carolina.

To enforce such an overall freeze at a level of $1.2 trillion would impose no intolerable hardships. Life would go on. The national security would be maintained; criminal laws would be enforced; the improving environment would be stable. By reducing some heavy expenses, such as farm subsidies, money could be found for such newly mandated entitlements as child care. The goal is the goal of Horatius: Hold the line!

Enough of these exhortations. The problem at bottom, as Bush well knows, is not that revenues are too small but that outlays are too large. The answer therefore -- an answer much easier to proclaim than to achieve -- is to cut spending until the country is prepared to pay as we go. That time will come within a few years if only Congress and the president will act responsibly. But if Congress is given new billions of dollars to play with, the day of a fairly balanced budget may never come at all.