Blackmun, dissenting (with WJB, TM, and JPS) in Commitee for Public Education v. Regan (1980)
http://caselaw.lp.findlaw.com/scripts/getcase.pl?court=us&vol=444&invol=646

I thought that the Court's judgments in Meek v. Pittenger, 421 U.S. 349 (1975), and in Wolman v. Walter, 433 U.S. 229 (1977) (which the Court concedes, ante, at 654, is the controlling authority here), at last had fixed the line between that which is constitutionally appropriate public aid and that which is not....

But, I repeat, the line, wavering though it may be, was indeed drawn in Meek and in Wolman, albeit with different [444 U.S. 646, 664]   combinations of Justices, those who perceive no barrier under the First and Fourteenth Amendments and who would rule in favor of almost any aid a state legislature saw fit to provide, on the one hand, and those who perceive a broad barrier and would rule against aid of almost any kind, on the other hand, in turn joining Justices in the center on these issues, to make order and a consensus out of the earlier decisions. Now, some of those who joined in Lemon, Levitt I, Meek, and Wolman in invalidating, depart and validate. I am able to attribute this defection only to a concern about the continuing and emotional controversy and to a persuasion that a good-faith attempt on the part of a state legislature is worth a nod of approval.

(emphasis added)