I came across an appellate brief in an interesting case recently: A.M. v. Taconic Hills Central School District, 2012 WL 1305401. At issue is a speech that an eighth grade student planned to give at her graduation, which she wanted to conclude with the following benediction from the Old Testament:
I say to you, may the LORD bless you and keep you; make His face shine upon you and be gracious to you; lift up His countenance upon you, and give you peace.The school district required her to remove the line, and her parents sued. I'll leave discussions about what Establishment Clause precedent says for others to address, and instead speak to what I think the proper result here would be.
It's undeniable that a graduation speech could be too strongly religious, in a way that would be an illegal governmental establishment of religion. Graduation speakers are given an endorsement by the school in virtue of a captive audience and an exclusive podium, even if the school disavows their message.
But if the quote above is all that the girl wanted to say, I don't see how it could be construed as an establishment. Beyond being monotheistic, it is a rather generic blessing. It is equitable and given freely to all (it does not, for instance, say: "may the LORD bless and keep the Christians"). And it is the kind of thing which only the very thin-skinned could take offense at.
The appellate brief is exactly right when it compares this case to politicians saying "God bless you, and God bless America." Unlike the identification of our nation as one "under God" in the Pledge of Allegiance or the declaration of a national trust in God on our currency, benedictions (well-wishing) ought not be banned by secularists of good will.