Moscow takes Reagan's radio gaffe seriously but not literally

Moscow has reacted to President Reagan's off-the-air joke about ''outlawing'' and ''bombing'' Russia with withering criticism - ''deploring'' his words while conceding that they could not be taken literally.

But behind the scenes, many in the Kremlin hierarchy are probably delighted that Mr. Reagan made such a verbal gaffe. It only helps their continuing campaign to depict him as dangerous.

Further, in the Kremlin view, it also yields insight into the President's true thinking and undercuts any claims he has made about trying to improve superpower relations. The remark gives the Kremlin a fresh opportunity to inject itself into the United States presidential election campaign.

Moscow's strongest reaction so far came in a statement by Tass, the Soviet news agency. Such statements represent official Kremlin thinking and are reserved for events deemed to be of major political significance.

Tass said it had been authorized to state that the Soviet Union deplores the comment, calling it ''unprecedentedly hostile toward the USSR and dangerous to the cause of peace.''

This conduct, according to Tass, ''is incompatible with the high responsibility borne by leaders of states, particularly nuclear powers....''

Tass said the episode should be ''seen as a manifestation of the self-same frames of mind'' which have led to confrontation with the Soviet Union.

The Kremlin is unlikely to let the matter rest there.

The President's words will most likely be reprinted innumerable times in an effort to stoke concerns - particularly in Europe - that Mr. Reagan could plunge the superpowers into outright hostilities.

''The policy of the incumbent US administration (is) extremely dangerous,'' said Tass, adding, ''no pseudo-peace rhetoric which from time to time is used in Washington for election-year purposes should mislead anyone. The fact that this rhetoric is not matched by real actions is obvious. If anyone has any doubts on this score, the latest 'frankness' of President Reagan should be an eye-opener for them as well.''

The President's verbal misstep comes at a particularly fortuitous time for the Kremlin.

The stationing of new NATO medium-range missiles in Western Europe is proceeding apace, despite the Kremlin's persistent efforts to block them.

Moscow is facing a nascent political coming-of-age in East Germany, where Communist Party leader Erich Honecker is showing an increasingly independent streak.

The Los Angeles Olympics, despite the Soviet-led boycott, were by and large viewed as successful.

And the new Soviet leader, Konstantin Chernenko, though undeniably more energetic than his immediate predecessors, has yet to claim credit for any major domestic or foreign policy breakthroughs. Moreover, East-West issues have not dominated the US presidential campaign, as the Kremlin might have hoped.