Until the tax man struck, the writers and artists who helped the New Yorker magazine become an American institution formed a relatively happy family.

Creators of the caliber of a John Updike, a Saul Steinberg, a John McPhee and dozens more could wield their pens with little fear of the dry spells and the Golden Years.

Since 1944 the magazine had maintained retirement and profit-sharing plans for its contract writers and artists - important elements for family happiness and productivity.

Then, after years of sanctioning the plans, the Internal Revenue Service in 1976 had a change of heart. IRS told the New Yorker that its plans would no longer qualify as apporved employe plans. No more profit-sharing, no more retirement pension.

The result, as New Yorker President George Green told a Senate subcommittee yesterday, was trauma in that happy, creative family of 105 artists affected by the IRS ruling.

"It caused quite a bit of distress in our orgainization," Green said. "More than one author decided he didn't want to work with us or submit work any longer."

Clearly, this represented a crisis situation, not just for the magazine, but for readers everywhere, and New York Sens. Jacob K. Javis (R) and Daniel Patrick Moynihan (D) rode to the rescue.

They introduced a bill that would overrule the IRS position and order, by act of Congress, that the writers and artists who hold renewable yearly contracts be considered New Yorker employes.

The bill would assure that the 105 who were participants until the plans were frozen at the end of 1977 would get their pensions and their shares of profits.

Green explained to Sen. Bob Packwood (R-Ore.), the lone Finance subcommittee member present, that the New Yorker's contractual arrangement with artists is a vital ingredient in keeping creative juices flowing.

"You can't tell writers and artists when to write or not write, when to draw or not draw," Green said in explaining why the magazine doesn't hire them as 9-to-5 employes.

Packwood, although not a New Yorker subscriber, said he saw justice in the magazine's plea. "If we can't work it out with the IRS, we'll work something out that is satisfactory to you," he said.

Quite obviously, an administration committed to human rights would not stand in the way of pensions and profit sharing, and so, to the surprise of Green and Packwood, the Treasury Department came out four-square for the bill.

Daniel I. Halperin, deputy assistant secretary of the treasury, testified that the administration approves of the bill and would actually broaden it.

Halperin suggested that it be expanded to include new writers and artists put under contract since the plans were frozen. Entirely reasonable, was the way he put it.

The muses smile.