New Jersey's Gov. Thomas H. Kean has on his desk a bill that would require public schools to set aside a minute of silence at the beginning of each school day. Sometime in the next week or so, he will decide whether to veto it or sign it into law.

Naturally he is not suffering from any shortage of advice on what to do. Is it stupidity on my part that keeps me from seeing what the problem is?

I understand clearly the problem with officially prescribed public school prayers -- even the ostensibly "voluntary" ones. It strikes me that even true believers who also believe in religious freedom would, if they really thought it through, see the danger of putting government authorities in charge of approving prayers.

But what is the danger in the moment's silence, originally proposed by Assemblyman James Zangari? The danger must be substantial, judging from the list of organizations calling for veto. They include the American Civil Liberties Union, the New Jersey Association of School Boards, the New Jersey Education Association, the Anti-Defamation League, the American Jewish Congress and the Association of School Administrators. Even the state Department of Education, which finds the proposed legislation "unnecessary." A number of newspapers have editorialized against it.

The New York Times, for example, observed last week: "The vacuity of a minute of silence gives it superficial innocence. But elsewhere, such laws have been abused. The American Jewish Congress cites an Oklahoma classroom in which the teacher announced the silent period by saying pupils could pray if they pleased, but added, 'Sam, you're Jewish. I don't think you pray.'"

But surely the problem there is the stupidity of a particular teacher, not the moment of silence.

Spoken prayers are a very different matter. Leave it to the children to compose their own prayers and you risk isolating and embarrassing those children who are not religious or who are adherents of minority religions. Leave it to the teacher or some other authority and you get either the same problem or else a prayer that is so innocuous as to be worthless.

But what is the offense in a minute of silence to be used, under the New Jersey proposal, "solely at the discretion of the individual student . . . for quiet and private contemplation or introspection"?

A federal district court held a similar law in Tennessee to be unconstitutional. Another federal district court upheld essentially the same law in Massachusetts. A trial is under way on New Mexico's minute-of-silence law, but Maine's similar statute apparently remains intact.

As far as I can tell, the principal fear is that approval of the minute of silence will embolden the religiously self- righteous to drop the other shoe: uttered prayers. It happened in Massachusetts, but the resulting voluntary- prayer legislation was ruled unconstitutional.

Assemblyman Zangari, who twice had earlier minute-of-silence proposals vetoed by former Gov. Brendan Byrne, says his legislation would "help children to have composure during the day (and) afford them an opportunity to calm down and relax."

Maybe it would, maybe it wouldn't. But it seems reasonably clear to me that it wouldn't do them any harm. And if it would make some devout people feel better, what, pray tell, is the problem?